In vitro research involving horses refers to the study of equine cells, tissues, or biological molecules outside their normal biological context, typically in controlled laboratory environments. This research approach allows scientists to investigate cellular processes, molecular interactions, and the effects of various treatments without the ethical and logistical complexities of in vivo studies. In vitro studies contribute to understanding equine physiology, pathology, and pharmacology by providing insights into cellular responses to pathogens, drugs, and other stimuli. This page compiles peer-reviewed research studies and scholarly articles that explore various in vitro methodologies and their applications in equine science, including cell culture techniques, molecular assays, and drug efficacy testing.
Haffner JC, Fecteau KA, Held JP, Eiler H.Under laboratory conditions and in clinical experiments, bacterial collagenase has proven to be effective in hydrolyzing placenta and detaching cotyledon from caruncle in the bovine species. Laboratory studies in which placental samples were incubated with collagenase have also demonstrated that collagenase is 3.7 times more effective in hydrolyzing equine placenta than bovine placenta. This led to the hypothesis that collagenase may be a potential treatment for mares with retained placenta. However, that collagenase may hydrolyze the uterine wall and perforate the uterus was a concern. It was...
Samper JC, Morris CA.Various factors affect the success of AI with frozen-thawed semen in horses. Stallion variability is thought to be one of the major factors, but semen processing and evaluation techniques, thawing protocols, packaging systems and timing of insemination are far from standardized among laboratories. Our objective was to survey current methods for stallion semen cryopreservation used commercially around the world. From the answers to the questions in the survey, we attempted to provide an overview of procedures that are standard as well as those that are used by only few laboratories and to revie...
Varner DD, Scanlan CM, Thompson JA, Brumbaugh GW, Blanchard TL, Carlton CM, Johnson L.Three experiments were conducted to evaluate the effects of different antibiotics in a milk-glucose semen extender on motility of equine sperm and elimination of bacteria following storage of extended semen in vitro. In Experiment 1, 7 antibiotics were compared: amikacin, gentamicin, streptomycin, potassium penicillin, sodium penicillin, ticarcillin, and polymixin B. In Experiment 2, 3 antibiotic treatments were compared: potassium penicillin G, amikacin, or a combination of potassium penicillin G and amikacin. In Experiment 3, 3 antibiotic treatments were compared: potassium penicillin G-amik...
Merkies K, Buhr MM.Spermatozoal function is affected by the ability to regulate intracellular calcium concentrations ([Ca2+]i), and may be influenced by epididymal maturation as well as environmental components. Regulation of [Ca2+]i in ejaculated and epididymal stallion spermatozoa was monitored over time in various media. Spermatozoa from each of 5 pony stallions (3 ejaculate samples and 1 caput and cauda sample) were labeled with the fluorescent calcium indicator probe Indo-1 in a calcium-free modified Tyrode's buffer. Fluorescent emissions were monitored by a dual wavelength spectrofluorometer over 5 h. Calc...
Shiue Y-L , Millon LV, Skow LC, Honeycutt D, Murray JD, Bowling AT.The hypothesis that the conservation of sex-chromosome-linked genes among placental mammals could be extended to the horse genome was tested using the UCDavis horse-mouse somatic cell hybrid (SCH) panel. By exploiting the fluorescence in-situ hybridization (FISH) technique to localize an anchor locus, X-inactivation-specific transcript (XIST) on the horse X chromosome, together with the fragmentation and translocation of the X- and Y-chromosome fragments in a somatic cell hybrid panel, we regionally assigned 13 type I and 13 type II (microsatellite) markers to the horse X- and Y-chromosomes. T...
Galuppo LD, Stover SM, Willits NH.To compare the biomechanical properties, in full limb preparations, of intact second phalanx and a simulated comminuted second phalangeal fracture stabilized with either two bone plates or a custom Y-plate. Methods: In vitro biomechanical assessment of intact limbs and of paired limbs with a simulated second phalangeal fracture stabilized by one of two fixation methods. Animal Population-Thirteen pairs of equine cadaveric forelimbs. Methods: A comminuted second phalangeal fracture was created in six paired cadaveric limbs. For each limb pair, the fracture was stabilized with two plates in one ...
McD￮ LA, Stover SM, Taylor KT.To determine cyclic biomechanical properties of gap osteotomized adult equine tibiae stabilized with an equine interlocking nail (EIN). Methods: In vitro experimental biomechanical investigation. Methods: Thirteen adult equine cadaveric tibiae. Methods: Adult equine tibiae with transverse, midshaft, 1-cm gap osteotomies, stabilized with an equine interlocking nail, underwent cyclic biomechanical testing in vitro under axial compression, 4-point bending, and torsion. Different specimens were subjected to different load levels that represented estimated in vivo loads at 2 Hz for 740,000 cycles. ...
Neild D, Chaves G, Flores M, Mora N, Beconi M, Agüero A.The aim of the study was to evaluate equine sperm membrane integrity using the hypoosmotic swelling (HOS) test and to correlate this test with different sperm parameters in raw and frozen thawed semen. The HOS solutions were made with fructose, sucrose, lactose and sodium citrate each at 300, 150, 100, 50 and 25 mosm. Maximum numbers of swollen spermatozoa were observed in solutions of fructose, sucrose and lactose each at 100, 50 and 25 mosm. Correlations between progressive motility, morphologically normal spermatozoa and the HOS test were r = 0.75 and r = 0.51 in raw semen and r = 0.26 and ...
Lindeberg H, Karjalainen H, Koskinen E, Katila T.A study was performed to test a new semen collection device (Equidame phantom) that fractionates the ejaculate by comparing the quality of semen obtained by the Equidame phantom with that obtained by a Missouri artificial vagina. Semen from 4 Finnhorse stallions was collected 4 times per stallion by both methods. Half of the ejaculate was frozen and the other half extended and loaded into 2 Equitainer transport containers (24- and 48-h samples). Motility parameters were determined by a Hamilton-Thorn motility analyzer after cooled storage for 24 and 48 h and again after freezing/thawing. Raw a...
Bedford SJ, Gowdy HL, Hinrichs K.This study was designed to compare the effects of different media and containers on longevity of motility of spermatozoa during in vitro incubation at 38 degrees C in either air or 5% CO2 atmosphere. Three ejaculates were collected from each of 4 stallions. The media tested were skim milk-glucose, modified Krebs/Ringer and Hank's salts solution for incubation in an air atmosphere, and modified Krebs/Ringer and Brackett and Oliphant (BO) defined medium for incubation in a 5% CO2 atmosphere. All samples were incubated in 5-mL borosilicate glass tubes filled with 3 mL of extended spermatozoa, 5-m...
Wierdl M, Morton CL, Danks MK, Potter PM.Butyrylcholinesterases (BuChEs; acylcholine acylhydrolase; EC 3.1.1.8) have been demonstrated to convert the anticancer agent CPT-11 (irinotecan, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin) into its active metabolite SN-38 (7-ethyl-10-hydroxycamptothecin). In addition, significant differences in the extent of drug metabolism have been observed with BuChEs derived from different species. In an attempt to understand these differences, we have isolated the cDNA encoding a horse BuChE. Based upon the NH2-terminal amino acid sequence of a purified horse BuChE, we designed deg...
Provitera P, Bouamr F, Murray D, Carter C, Scarlata S.Human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) are closely related lentiviruses that infect immune cells, but their pathogenesis differ. Localization to the cytosolic leaflet of the plasma membrane is critical for replication of both viruses. This localization is accomplished through the matrix (MA) domain of the Gag precursor protein. In HIV-1, association of MA to anionic membranes appears to be primarily driven by a linear cluster of basic residues in the MA domain and an N-myristoylation signal. Interestingly, the MA protein of EIAV does not contain either of ...
Molenkamp R, Rozier BC, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the type member of the family Arteriviridae, is a single-stranded RNA virus with a positive-stranded genome of approximately 13 kb. EAV uses a discontinuous transcription mechanism to produce a nested set of six subgenomic mRNAs from which its structural genes are expressed. We have generated the first documented arterivirus defective interfering (DI) RNAs by serial undiluted passaging of a wild-type EAV stock in BHK-21 cells. A cDNA copy of the smallest DI RNA (5.6 kb) was cloned. Upon transfection into EAV-infected BHK-21 cells, transcripts derived from this clo...
Barber MR, Fayrer-Hosken RA.Ecological and conservation programs in ecosystems around the world have experienced varied success in population management. One of the greatest problems is that human expansion has led to the shrinking of wildlife habitat and, as a result, the overpopulation of many different species has occurred. The pressures exerted by the increased number of animals has caused environmental damage. The humane and practical control of these populations has solicited the scientific community to arrive at a safe, effective, and cost-efficient means of population control. Immunocontraception using zona pellu...
Argenzio RA.Ulceration of the nonglandular, stratified squamous mucosa of the equine and porcine stomach is a common event in both species, although in pigs the fatality rate is significant and it is an economically important disease. Because the barrier function of this mucosa in horses and pigs appears similar, it is probable that similar pathophysiological mechanisms may be responsible for the initiating lesions and reparative events. Recent studies of ulcer pathogenesis in the pig have shown that feed preparation or prolonged fasting can result in disruption of the normal stratification of gastric con...
Berschneider HM, Blikslager AT, Roberts MC.Gastric contents were sampled in horses via nasogastric tube to determine changes in pH and bile salt concentrations during feeding and fasting periods. The horses were rotated through 4 feeding protocols. (1) hay; (2) hay with twice daily grain meals; (3) and (4) fasting preceded by either hay only or hay and grain. Sequential, hourly samples were collected from 3 horses prepared with gastric cannulas. Horses were fed hay twice daily and grain mix either twice daily or in small aliquots dispensed every 90 min. The horses were sampled during normal feeding or after 14 h of feed deprivation. Ga...
Aggarwal N, Holmes MA.Despite the importance of IgG Fc receptors in the regulation of various immunological mechanisms, these receptors have not been well characterised in the domesticated animals including equines. This paper describes the production of two monoclonal antibodies (CVS 59 and CVS 61) that recognise equine IgG Fc receptors. Fusions were conducted using BALB/c mice hyperimmunised with equine peripheral blood mononuclear cells. Hybridoma supernatants were screened on the basis of their ability to inhibit the rosetting of equine antibody coated sheep erythrocytes with equine peripheral blood mononuclear...
Beech J, Fletcher JE, Erwin K, Lindborg SR.To determine sensitivity of equine skeletal muscle to tetrodotoxin and compare that with sensitivity of murine and human skeletal muscles. Methods: Semimembranosus, vastus lateralis, triceps brachii, and masseter muscle specimens from 22 euthanatized horses, vastus lateralis muscle biopsy specimens from 25 clinically normal humans, and diaphragmatic muscle specimens from 6 mice. Methods: Electrically elicited twitch responses were measured in muscle specimens incubated in medium alone and with tetrodotoxin (100 nM, 400 nM, 1.6 microM for equine specimens and 100 nM, 200 nM, 400 nM, 800 nM, 1.6...
Siedek EM, Honnah-Symns N, Fincham SC, Mayall S, Hamblin AS.Monoclonal antibodies (mAbs) recognizing equine macrophages are scarce. The present study compared the immunocytochemical staining of various equine tissues (lymphoid tissue, lung, liver, small intestine, skin and blood leucocytes) by an antibody, Ki-M6, which detects CD68 in human macrophages and dendritic cells, and by a new anti-equine mAb, JB10, with staining produced by two previously described anti-equine macrophage mAbs, CZ2.2 and CZ3.3. Ki-M6 was shown to identify equine macrophages, which had a distribution different from those identified by CZ2.2 and CZ3.3. JB10 identified equine mac...
Cho HJ, Entz SC, Deregt D, Jordan LT, Timoney PJ, McCollum WH.A potent ELISA antigen was prepared from equine arteritis virus (EAV) by differential centrifugation of EAV-infected cell culture fluid, followed by solubilization of the preparation by Triton X-100 treatment. Using this antigen and a mouse monoclonal antibody against the G(L) protein of EAV, a reliable blocking ELISA (bELISA) was developed for the detection of EAV antibodies in equine sera. The bELISA was evaluated using a total of 837 test serum samples. The relative sensitivity (n = 320) of the bELISA compared to the serum neutralization (SN) test was 99.4%. The bELISA appears to be a highl...
The Journal of physiologyFebruary 16, 2000
Volume 523 Pt 1, Issue Pt 1 131-138 doi: 10.1111/j.1469-7793.2000.t01-3-00131.x
Wang YX, Kotlikoff MI.1. The signalling pathway underlying histamine activation of non-selective cation channels was investigated in single equine tracheal myocytes. Application of histamine (100 microM) activated the transient calcium-activated chloride current (ICl(Ca)) and sustained, low amplitude non-selective cation current (ICat). The H1 receptor antagonist pyrilamine (10 microM) blocked activation of ICl(Ca) and ICat. Simultaneous application of histamine (100 microM) and caffeine (8 mM) during H1 receptor blockade activated ICl(Ca), but not ICat. Neither the H2 receptor antagonist cimetidine (20 microM) nor...
Parker NA, Bailey TL, Bowen JM, Ley WB, Purswell BJ, Dascanio JJ.Like the human female, the mare experiences reproductive tract pathology that may sometimes be circumvented by the use of assisted reproductive technologies (ARTs). One such technology, gamete intrafallopian transfer (GIFT), may be used in mares that exhibit ovulatory, oviductal, or uterine abnormalities that limit the use of common ARTs, such as embryo transfer. Homologous GIFT has been successfully performed in the horse; however, the logistics, costs, and associated risks of surgically transferring gametes to the oviducts of a recipient mare are considerably high. Use of a less costly speci...
Schumacher J, Wilson AM, Pardoe C, Easter JL.A prosthesis, composed of a steel cable and stress-reducing washers, was developed to prevent failure of laryngoplasty, a common treatment for horses affected by recurrent laryngeal neuropathy. Laryngoplasties were performed on 15 cadaveric larynges using a polyester suture on one side and the cable prosthesis on the other. Each prosthesis was distracted at a displacement rate of 20 mm/s using a servohydraulic materials testing machine until laryngoplasty failed. Distraction force and actuator displacement were recorded and analysed. All 15 laryngoplasties performed with a suture failed at the...
Väihkönen LK, Hyyppä S, Reeta Pösö A.In horses, both the post exercise distribution of lactate between plasma and red blood cells (RBC) and the activity of lactate transporters on the RBC membrane vary widely between individuals. In this study, we investigated the effects of pH, time and temperature on lactate distribution in vitro, and compared the in vitro activity of lactate transporters with the accumulation of lactate into RBC in vivo. To accomplish this, we took venous blood samples at rest and after trotting races. The post exercise accumulation of lactate into RBC was shown to depend on the activity of lactate transporter...
Willemen MA, Jacobs MW, Schamhardt HC.An in vitro model was developed and validated in vivo to quantify the attenuation of impact vibrations, transmitted through the lower equine forelimb and to assess the effects of horseshoeing on this attenuation. The transsected forelimbs of 13 horses were equipped with custom-made hollow bone screws in the 4 distal bones, on each of which a tri-axial accelerometer could be mounted. The limbs were then preloaded while the impact was simulated by dropping a weight on the steel plate on which the hoof was resting. At the hoof wall, the distal, middle and proximal phalanx and at the metacarpal bo...
McD￮ LA, Stover SM, Bach JM, Taylor KT.To determine the mechanical properties of Equine Interlocking Nail (EIN; JD Wheat Veterinary Orthopedic Research Laboratory, University of California, Davis) stabilized osteotomized tibiae and compare these variables with estimated in vivo loads. Methods: In vitro biomechanical investigation. Methods: Twelve adult equine cadaveric tibiae. Methods: EIN-stabilized tibiae were tested monotonically under compression, 3- and 4-point bending, and torsion. Mechanical properties were compared with estimated in vivo loads. Results: EIN-tibial composite mean compressive yield load (11 kN) and bending mo...
Miller CB, Wilson DA, Keegan KG, Kreeger JM, Adelstein EH, Ganjam VK.To determine if there is a difference in in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. To determine the effects of a corticosteroid and monokine on in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. Methods: Growth of fibroblasts from tissues harvested from the trunk and limb were compared from horse and pony samples grown in control media and control media with triamcinolone or monokine added. Methods: Dermal and subcutaneous tissue from 22 horses and 17 ponies of various ages ...
Mungall BA, Pollitt CC.To investigate the role of matrix metalloproteinase (MMP) activity in the pathophysiology of equine laminitis, the techniques of in situ zymography and quantitative SDS-PAGE zymography were used to analyse the lamellae and plasma and serum of horses with carbohydrate overload-induced laminitis. The gelatinase activity localised within the epidermal lamellae of laminitic hooves did not differ significantly from normal hooves. In laminitis sections there was an increase in vascular gelatinase activity, possibly associated with the perivascular cuffing of polymorphonucleocytes. Both plasma and se...
Svistunenko DA, Sharpe MA, Nicholls P, Wilson MT, Cooper CE.A new method of EPR spectral analysis is developed to quantitate overlapping signals. The method requires double integration of a number of spectra containing the signals in different proportions and the subsequent solution of a system of linear equations. The result gives the double integral values of the individual lines, which can then be further used to find the concentrations of all the paramagnetic species present. There is no requirement to deconvolute the whole spectrum into its individual components. The method is employed to quantify different heme species in methemoglobin and metmyo...
Chang YF, Novosol V, McDonough SP, Chang CF, Jacobson RH, Divers T, Quimby FW, Shin S, Lein DH.Seven specific-pathogen-free (SPF) ponies, 1-5 years old, were exposed to Borrelia burgdorferi-infected adult ticks while being treated with dexamethasone over 5 consecutive days. One SPF pony (pony No. 178) was first exposed to laboratory-reared nymphs without B. burgdorferi infection and 3 weeks later was exposed to B. burgdorferi-infected adult ticks with concurrent dexamethasone treatment for 5 consecutive days. Four uninfected ponies treated with dexamethasone, exposed to laboratory-reared ticks without B. burgdorferi infection served as uninfected controls. Clinical signs, bacteriologic ...
Brown KA, Boerboom D, Bouchard N, Doré M, Lussier JG, Sirois J.17Beta-hydroxysteroid dehydrogenase type 4 (17betaHSD4) has a unique multidomain structure, with one domain involved in 17beta-estradiol inactivation. The objective of the study was to investigate the regulation of 17betaHSD4 during human chorionic gonadotropin (hCG)-induced ovulation/luteinization. The equine 17betaHSD4 cDNA was cloned and was shown to encode a 735-amino acid protein that is highly conserved (81-87% identity) compared with other mammalian orthologs. RT-PCR/Southern blot analyses were performed to study the regulation of 17betaHSD4 transcripts in equine preovulatory follicles ...
Sod GA, Riggs LM, Mitchell CF, Martin GS.To compare in vitro monotonic biomechanical properties of an axial 3-hole, 4.5 mm narrow locking compression plate (ELCP) using 5.0 mm locking screws and 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion (ELCP-TLS) with an axial 3-hole, 4.5 mm narrow dynamic compression plate (DCP) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion (DCP-TLS) for equine proximal interphalangeal (PIP) joint arthrodesis. Methods: Experimental. Methods: Cadaveric adult equine forel...
Patton ME, Andrews FM, Bogers SH, Wong D, McKenzie HC, Werre SR, Byron CR.Ileus is a common life-threatening problem in horses, and currently available treatments may be ineffective. The purpose of this study was to determine whether bit chewing, a form of sham feeding, decreases the gastric emptying time (GET), small intestinal transit time (SITT), and total orocecal transit time (OCTT) in clinically normal horses in a prospective crossover study. Nine healthy horses were acclimated and fed a standardized diet. Following 24 h of fasting, self-contained video endoscopy capsules and acetaminophen were administered into the stomach via a nasogastric tube. Each horse u...
Jones I, Madej A.Microtitre plates were coated with antiserum against oestradiol-17 beta-6-(O-carboxymethyl)-oxime bovine serum albumin raised in sheep. The plasma samples (0.2-1.0 ml) were extracted with peroxide-free diethyl ether prepared daily by treatment with Al2O3. The enzyme conjugate was prepared by coupling oestradiol-17 beta-6-(O-carboxymethyl)-oxime to horse-radish peroxidase. The conjugate was chromatographed on a Sephadex G-25 column. The standard curve ranged from 0.37 to 18.40 fmol/well of oestradiol-17 beta. The amount of oestradiol-17 beta causing a 50% reduction of maximum binding was 4.4 fm...
Silver IA, Eisinger M.We have examined the possible regulatory role of epidermal cell extract(s) (ECE) on skin cells, namely fibroblasts and keratinocytes, both in vivo and in vitro with particular reference to modification of scar formation. In an experimental wound model in pigs, it was found that extracts of cultured human and pig keratinocytes stimulated replication of epidermal cells and their migration from wound edges and remnants of hair follicles and sebaceous glands, together with hair growth, but at the same time suppressed fibroblast proliferation in the dermis. Sections of healing skin wounds that had ...
Farrar RG, Klei TR.Strongylus edentatus was successfully cultured in vitro to the fourth larval stage (L4). Some growth continued for periods of 40-50 days at which time reductions in viability were observed in some of the culture systems tested. Various combinations of media, sera, buffers and organ explant cultures were tested. All cultures were incubated at 37 C in an atmosphere of 95% air and 5% CO2. Larvae underwent growth and differentiation to the L4 in all medium-serum combinations with and without organ explant cultures. Development and growth did occur but viability was reduced to insignificant levels ...
Bousfield GR, Liu WK, Ward DN.LH hybrids were prepared by combining eLH alpha and eLH beta with the corresponding subunits of oLH, pLH and hCG. Recombinants were isolated by gel filtration and assessed by SDS-polyacrylamide gel electrophoresis under both dissociating and non-dissociating conditions. All combinations of subunits produced hybrid LH molecules. Hybrids prepared by combining eLH beta with oLH alpha, pLH alpha or hCG alpha were very inactive in rat radioligand and Leydig cell in vitro bioassays. Hybrids prepared with eLH alpha were very active in both assays. The greatest potentiating activity was observed when ...
Moiseeva SA, Postnikova GB.The influence of Cu2+ concentration, pH, and ionic strength of the solution as well as redox-inactive zinc ions on the rate of oxidation of sperm whale, horse, and pig oxymyoglobins (oxy-Mb) by copper ions has been studied. These myoglobins have homologous spatial structures and equal redox potentials but differ in the number of histidines located on the surface of the proteins. It was shown that oxy-Mb can be oxidized in the presence of Cu2+ through two distinct pathways depending on which histidine binds the reagent and how stable the complex is. A slow pH-dependent catalytic process is obse...
Jolly RD, Dalefield RR.The lipopigments are a heterogenous group of pigments whose pathogenesis and terminology is confused. Whereas there is epidemiological and observational evidence that ceroid is derived from degeneration and peroxidation of unsaturated lipid, the assumption that all so-called lipopigments are similarly formed, is questioned. In particular, recent studies have distanced the pathogenesis of the pigment found in the ceroid-lipofuscinoses from that perceived for ceroid. The importance of protein rather than lipid in the pathogenesis of the pigment of ceroid-lipofuscinosis and of age pigment from th...
Galbraith EA, McKellar QA.Flunixin was highly protein bound in the serum of dogs (92.2 per cent), goats (84.8 per cent) and horses (86.9 per cent). Meclofenamic acid was also highly protein bound, although there were larger differences between the extent of the binding in dogs (90.3 per cent), goats (84.7 per cent) and horses (99.8 per cent). Both flunixin and meclofenamic acid were potent inhibitors of the in vitro generation of thromboxane (Tx) B2 in blood. Flunixin inhibited the generation of TxB2 by 50 per cent of the maximum response (IC50) in dog, goat and horse blood at concentrations of 0.10, 0.02 and 0.04 micr...
Richard F, Martinat N, Remy JJ, Salesse R, Combarnous Y.Among all mammalian FSH receptors (FSH-R; including donkey (dk) FSH-R), only horse (hs) FSH-R does not bind hsLH/chorionic gonadotrophin (CG). In order to delineate the structural origin of hsFSH-R specificity precisely, we have cloned dkFSH-R cDNA from donkey testis mRNA by RT-PCR. Transiently expressed dkFSH-R endowed COS-7 cells with both hsLH/CG- and FSH-binding activity, as well as FSH-induced cAMP production. The deduced dkFSH-R amino acid sequence shares 96% identity with the hsFSH-R: notably, in the hormone-binding domain, the specificity of hsFSH-R may be ascribed to only four diverge...
Shiels IA, Sanderson SD, Taylor SM.To develop an in vitro model of uveitis based on an ex situ perfused eye to evaluate the anti-inflammatory activity of new pharmacological products. Methods: Eyes were removed from more than 60 dogs and 9 horses immediately after euthanasia and perfused with nutrient medium through the lateral long ciliary artery. Perfused eyes produced aqueous humour, and perfusion pressure was adjusted to obtain an intraocular pressure in the physiological range. When the eyes were treated with histamine, a complement C5a analogue peptide and hydrogen peroxide, typical signs of uveitis were produced. These i...
Sedgwick AD, Lees P, Dawson J, May SA.The migration of leucocytes to sites of acute and chronic inflammation is an event of central importance to the maintenance of inflammatory processes; extravascular leucocytes are responsible for generating chemical mediators of inflammation and the phagocytosis of particulate matter. They may also be involved in the conversion of acute to chronic inflammatory lesions. Leucocytes are attracted to sites of tissue injury by a range of chemoattractants. This paper describes the development of a method for separating on Percoll gradients purified populations of equine polymorphonuclear and mononuc...
Charbord P, Tippens D, Wight TS, Gown AM, Singer JW.This report describes an IgG1 mouse monoclonal antibody derived after immunization of mice with washed stromal cells from human, long-term bone marrow cultures. The antigen recognized by the antibody (BMS-1) is a carbohydrate-containing prosthetic group that is common to and specific for multiple horse serum proteins. These proteins are avidly ingested by stromal cells and concentrated in endocytic vesicles. Cultured smooth muscle cells took up the horse proteins in a similar manner to marrow stromal cells while cultured marrow fibroblasts, endothelial cells, and hepatoma cells did not. These ...
Ishiyama T, Shinagawa M, Sato G, Fujinaga K, Padmanabhan R.Equine adenovirus (EAd) DNA prepared from infected bovine kidney (MDBK) cells contained additional sequences of about 100 to 700 bp at the left-hand end of the genome. These aberrant viral genomes were produced even after the first passage of the wild type EAd in MDBK cells and their relative amounts did not change significantly during serial passage. The left terminal fragments of two defective viral DNAs were cloned into the plasmid vector pBR322 and the nucleotide sequences of their terminal regions were analyzed. The data indicate that one viral DNA contained a duplication of the inverted ...
Chapus C, Desnuelle P, Foglizzo E.Pig and horse colipases have been purified by a common procedure using trypsin and carboxypeptidase inhibitors as stabilizers. Two forms of pig colipase were identified: a predominant A1 form with about 103-105 residues, and a minor slightly degraded A2 form in which the last two C-terminal residues, Asp and Ser, were lacking. This type of degradation is considerably slowed down by carboxypeptidase inhibitors. A total of four forms of the horse cofactor were characterized: two (A1 and B1) were probably isocolipases which differed by only a few substitutions. Both contained the same number of r...
Brütsch DR, Hunziker P, Pot S, Tappeiner C, Voelter K.Intraocular fibrin clots caused by severe uveitis can be a sight-threatening condition that needs to be resolved quickly and reliably. Intracameral injection of tissue-plasminogen activator (tPA) is commonly used to resolve intraocular fibrin. However, the drug does not reach fibrinolytic concentrations after topical application. Desmoteplase (DSPA) is a structurally similar but smaller fibrinolytic agent with a higher fibrin selectivity, a longer half-life, and better biocompatibility compared with tPA. This study was designed to evaluate the corneal and scleral permeability of DSPA in rabbit...
Shibany KA, Pratt SL, Aldurdunji M, Totemeyer S, Paine SW.Horses are exposed to various kinds of medication, however, there are limited determinations of plasma clearance (CL) for the drugs used due to the high cost of equine studies.Many of the CL values generated come from the equine sports industry for determining drug plasma screening limits in the control of medications at the time of competition.The kinetics of omeprazole metabolism were investigated in freshly isolated and cryopreserved equine hepatocytes and hepatic microsomes ( = 3 horses).The V, K and intrinsic clearance (CL) of omeprazole were determined via the substrate depletion me...
Singha H, Goyal SK, Malik P, Singh RK.Thermostabilizing effect of heavy water (D2O) or deuterium oxide has been demonstrated previously on several enzymes and vaccines like oral poliovirus vaccine and influenza virus vaccine. In view of the above observations, effect of heavy water on in situ thermostabilization of recombinant p26 protein on enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of equine infectious anemia virus (EIAV) infection was investigated in the present study. The carbonate-bicarbonate coating buffer was prepared in 60% and 80% D2O for coating the p26 protein in 96-well ELISA plate and thermal stabilit...
O'Donovan LH, McMonagle EL, Taylor S, Argyle DJ, Nicolson L.Interleukin 18 (IL-18) is a cytokine capable of induction of IFNgamma, granulocyte monocyte-colony stimulating factor (GM-CSF), TNFalpha and IL-1 in immunocompetent cells. Equine and feline plasmid vectors expressing pro-IL-18, mature IL-18 and IL-18 fused to a synthetic signal sequence from human IL-1beta receptor antagonist protein (ILRAP), ILRAP-IL-18, have been generated. In vitro protein expression of these constructs was compared by Western blot analysis. These data demonstrated that ILRAP-IL-18 protein was secreted readily from transfected chinese hamster ovary (CHO) cells. A simple bio...
Ward RJ, Ramsey M, Dickson DP, Hunt C, Douglas T, Mann S, Aquad F, Peters TJ, Crichton RR.The biochemical and biophysical properties of isolated haemosiderins have been compared to that of another iron-containing protein, termed prehaemosiderin, which sediments through chaotropic potassium iodide only after 20 h of ultracentrifugation, in contrast to that of haemosiderin which is recovered after 2 h of ultracentrifugation. The iron/protein ratio and iron/phosphate ratio were less that that of the corresponding haemosiderin, while the elemental composition was also reduced in many of the prehaemosiderin samples. Mossbauer spectroscopy and electron diffraction identified the predomin...
Lin Y, Deng X, Shen N, Zhao L, Meng Q, Max J, Wang J, Shao Y, Zhou J.The attenuated vaccine of equine infectious anemia virus (EIAV) is the first lentiviral vaccine that provides solid protection against the infection of EIAV virulent strains. Study of the immune response induced by EIAV vaccine is an important approach to understand the immunity to other lentiviruses. IFN-gamma expressed by specifically stimulated lymphocytes is an important indicator for the evaluation of T cell-mediated immunity. A flow cytometry based assay was established in this study to accurately and effectively detect IFN-gamma expression in different subtypes of T lymphocytes in EIAV-...
Patan-Zugaj B, Egerbacher M, Licka TF.Angiogenesis and sepsis-related equine laminitis have several features in common. Both events can be induced by endotoxin (lipopolysaccharide- LPS) and both are associated with increased expression of the enzyme cyclooxygenase (COX), of which two isoforms (COX-1 and COX-2) exist. To examine the causal relationship between LPS exposure and COX expression and to investigate the tissue distribution of COX in the LPS-exposed tissue, the technique of extracorporeal haemoperfusion of isolated equine forelimbs was utilized. Perfusion was performed for 10 hr under physiological conditions (control-pe...
The Journal of physiologyDecember 1, 1996
Volume 497 ( Pt 2), Issue Pt 2 349-364 doi: 10.1113/jphysiol.1996.sp021773
Hanna WJ, Tsushima RG, Sah R, McCutcheon LJ, Marban E, Backx PH.1. The Na+ channel mutation associated with equine hyperkalaemic periodic paralysis (HPP) affects a highly conserved phenylalanine residue in an unexplored region of the alpha-subunit. This mutation was introduced into the rat skeletal muscle Na+ channel gene at the corresponding location (i.e. F1412L) for functional expression and characterization in Xenopus oocytes. 2. In comparison with wild-type (WT) channels, equine HPP channels showed clear evidence for disruption of inactivation: increased time-to-peak current, slowed rates of whole-cell current decay, significant increases in sustained...
Prickett TCR , Inder WJ, Evans MJ, Donald RA.The acute-phase cytokine interleukin-1 (IL-1) is known to activate the hypothalamic pituitary adrenal axis, primarily via corticotropin releasing hormone (CRH). The aim of this study was to determine whether IL-1beta could directly stimulate ACTH secretion from perifused equine anterior pituitary cells, and whether CRH pre-incubation affected corticotroph responsiveness. Isolated equine anterior pituitary cells were pre-incubated with media containing 10 nM CRH or vehicle for 20 hours before being loaded onto columns and perifused with 0.02 nM CRH and 100 nM cortisol. Columns were given a 5-mi...
Hochi S, Fujimoto T, Choi YH, Braun J, Oguri N.Immature equine oocytes were frozen-thawed with ethylene glycol (EG), 1,2-propanediol (PD) or glycerol (GL) in PBS and cultured to assess the rate of in vitro maturation (Experiment 1). Compact-cumulus oocyte complexes were collected from slaughterhouse ovaries and equilibrated for 10 min in the freezing medium containing 10% (V/V) cryoprotectant and 0.1 M sucrose. The 0.25-ml straws, loaded with 10 to 30 oocytes, were seeded at -6 degrees C and cooled to -35 degrees C at 0.3 degrees C/min before being plunged into liquid nitrogen. The straws were thawed rapidly in a 37 degrees C waterbath for...
Gim JA, Kim HS.MicroRNAs (miRNAs) are single-stranded, small RNAs (21-23 nucleotides) that function in gene silencing and translational inhibition via the RNA interference mechanism. Most miRNAs originate from host genomic regions, such as intergenic regions, introns, exons, and transposable elements (TEs). Here, we focused on the palindromic structure of medium reiteration frequencies (MERs), which are similar to precursor miRNAs. Five MER consensus sequences (MER5A1, MER53, MER81, MER91C, and MER117) were matched with paralogous transcripts predicted to be precursor miRNAs in the horse genome (equCab2) and...
Mukhtar AH, Alqutub MN.The aim of this study was to compare between equine and human bone blocks in the osteogenic differentiation of cultured human periodontal ligament stem cells (hPDLSCs) at 14 and 21 days of culture, using confocal laser microscopy and scanning electron microscopy. Methods: cultures of commercially obtained hPDLSCs were seeded onto equine and human bone blocks. At 14 days and 21 days of culture, confocal laser microscope images were obtained to assess cellular differentiation and adhesion, and scanning electron microscope images were obtained to validate the osteogenic differentiation by showin...
Evans MJ, Marshall AG, Kitson NE, Summers K, Donald RA.The multifactorial control of ACTH is well established. We wished to establish and characterize an in-vitro perifusion system, using equine anterior pituitary cells and physiological concentrations of secretagogues, to investigate factors which affect the dynamics of ACTH secretion. Anterior pituitary tissue was divided for dispersion into cells with collagenase, trypsin or dispase, or by mechanical dispersion. After dispersal followed by 18-h incubation, cells were perifused and the ACTH response to 10-min pulses of arginine vasopressin (AVP; 100 nmol/l), corticotrophin-releasing hormone (CRH...
Staczek J, Wharton JH, Dauenhauer SA, O'Callaghan DJ.Semipermissive, primary hamster embryo (HE) cells were morphologically transformed in vitro by infection with UV-irradiated equine cytomegalovirus (equine herpesvirus type 2; ECMV). Cell lines (designated EC-1-3) were established independently from foci and were shown to exhibit growth and biological properties typically associated with transformed cells: altered morphology, loss of contact inhibition, increased saturation density, decreased generation time, immortality in culture, normal growth in low concentrations of serum, colony formation in soft agar, and resistance to ECMV superinfectio...
