Proteins are essential macromolecules that play diverse roles in the physiology and health of horses. They are composed of amino acids and are involved in various biological processes, including tissue growth, repair, and the synthesis of enzymes and hormones. Dietary proteins are a key component of equine nutrition, influencing muscle development, immune function, and overall performance. Horses require a balanced intake of essential amino acids, which must be obtained through their diet, as they cannot be synthesized endogenously. This page compiles peer-reviewed research studies and scholarly articles that explore the types, functions, and dietary requirements of proteins in horses, as well as their impact on equine health and performance.
Wasfi IA, Abdel Hadi AA, Elghazali M, Boni NS, Alkatheeri NA, Barezaig IM, Al Muharami AM, Hamid AM.The pharmacokinetics of tripelennamine (T) was compared in horses (n = 6) and camels (n = 5) following intravenous (i.v.) administration of a dose of 0.5 mg/kg body weight. Furthermore, the metabolism and urinary detection time was studied in camels. The data obtained (median and range in brackets) in camels and horses, respectively, were as follows: the terminal elimination half-lives were 2.39 (1.91-6.54) and 2.08 (1.31-5.65) h, total body clearances were 0.97 (0.82-1.42) and 0.84 (0.64-1.17)L/h/kg. The volumes of distribution at steady state were 2.87 (1.59-6.67) and 1.69 (1.18-3.50) L/kg, ...
Sutcliffe IC, Trigg J, Harrington D.Using preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp. equi. N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). Interestingly, the only form of the HPr protein detected in S. equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins.
Hamilton A, Harrington D, Sutcliffe IC.Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resis...
Retamal C, Urzúa J, Lorca C, López ML, Alves EW.The present paper reports modifications in the electrophoretic and cytochemical characteristics of mature and immature stallion spermatozoa. Some sperm surface glycoproteins (36, 32, 29, 21, 20, 18 kDa) detected in cauda epididymidis spermatozoa, were either absent or present in a very low relative concentration in immature sperm cells. A major 14 kDa protein band, observed in sperm extracts obtained from ductus efferentes, progressively decreased along the epididymal ductus. The nature and distribution of carbohydrate residues on the sperm membrane, during epididymal maturation, was also stud...
Stewart F, Kennedy MW, Suire S.Horses, donkeys, and therefore, probably all equids, secrete a nonglycosylated, progesterone-dependent, 19-kDa protein (P19) into the uterine lumen during early pregnancy, and significant quantities of it are taken up by the developing conceptus. Sequence analysis and structural modelling have identified P19 as a lipocalin with greatest similarity to the murine major urinary protein lipocalins. However, lack of strong identity with any particular group of lipocalins and several unusual structural features, including a unique amino acid triplet within one of the invariant domains and an unusual...
Riond JL, Leoni S, Wanner M.Three feeding methods were compared in 36 4- to 6-year-old Franche-Montagne horses during the military school of St-Luzisteig (GR) of Spring 1992. The horses were separated into 3 groups: a group with the traditional oats-hay ration (OH), a group with a pelleted feed and hay ration (PFH), and a group with the complete diet (CD). Feed analyses were performed and food consumption, eating behavior and digestibility were studied. The horses received their daily amount of feed in 3 portions covering the requirements for a medium work: OH = 8 kg hay and 3 kg oats, PFH = 8 kg hay and 3 kg pelleted fe...
Taylor KC, Vitello LB, Erman JE.The ionization of 4-nitroimidazole to 4-nitroimidazolate was investigated as a function of ionic strength. The apparent pKa varies from 8.99 to 9.50 between 0.001 and 1.0 M ionic strength, respectively, at 25 degrees C. The ionic strength dependence of this ionization is anomalous. The binding of 4-nitroimidazole by horse metmyoglobin was studied between pH 5.0 and 11.5 and as a function of ionic strength between 0.01 and 1.0 M. The association rate constant is pH-dependent, varying from 24 M(-1)s(-1) at pH 5 to a maximum value of 280 M(-1)s(-1) at pH 9.5 and then decreasing to 10 M(-1)s(-1) a...
Svistunenko DA, Sharpe MA, Nicholls P, Blenkinsop C, Davies NA, Dunne J, Wilson MT, Cooper CE.The paramagnetic species in human metHb and horse metmyoglobin (metMb) have been studied at low temperature using EPR spectroscopy. The high-spin (HS) haem signal in aquometMb has a greater rhombic distortion than the HS metHb signal. Nevertheless, the individual line width (g=6) is smaller in metMb than in metHb, consistent with non-identical signals from the alpha and beta Hb subunits. Three low-spin (LS) haem forms are present in metHb, while metMb has only two. The major LS form in both proteins is the alkaline species (with OH(-) at the sixth co-ordination position). The minor LS forms ar...
Frisbie DD, McIlwraith CW.Joint disease in horses and in humans is a significant social and economic problem and continued research and improvements in therapeutics are needed. Because horses have naturally occurring osteoarthritis that is similar to that of humans, the horse was chosen as a species to investigate gene transfer as a potential therapeutic modality for the treatment of osteoarthritis. Using an established model of equine osteoarthritis, the therapeutic effects resulting from overexpression the equine interleukin-1 receptor antagonist gene sequence through adenoviral mediated gene transfer was investigate...
Greenaway EC, Cunningham FM, Goode NT.Phorbol esters, which activate protein kinase C (PKC), stimulate equine eosinophil superoxide production and adherence. After showing that superoxide production could be inhibited by the nonselective PKC inhibitors, staurosporine and bisindolymaleimide I, the PKC isotypes in equine eosinophils were characterized, because evidence suggests that individual isotypes may play distinct roles in regulating eosinophil function. Western blots demonstrated that equine eosinophils expressed PKC alpha, beta, delta, epsilon, iota, and zeta. However, unlike the equine neutrophil, the majority of the PKC wa...
Byrne KM, Vierck J, Dodson MV.Equine satellite cells are responsible for muscle healing and regeneration in the mature horse. We describe the in vitro cell culture conditions required for clonal populations of equine satellite cells to undergo both proliferation and differentiation. Our hypothesis is that these in vitro conditions model regeneration of muscle and can be used to evaluate potential therapeutics. In this study, 2 areas of satellite cell response were tested: proliferation of clones induced by growth factors, and fusion induced by culture conditions. Equine satellite cell clones showed differences in their res...
Hallebeek JM, van Doorn DA, Beynen AC.In horses that exercise intensively (for example, event horses in training) the intake and energy requirements were compared on the basis of a diet record and estimates of energy required for exercise. Daily net energy intake over a 7 days period was on average 30% (n = 15) higher than the net energy requirement. Since the horses had a constant body weight, and thus were in energy balance, the energy intake was overestimated and/or the energy requirement was underestimated. The intake of digestible protein was 92% higher than the protein requirement. This study illustrates the problems concern...
Harrington DJ, Greated JS, Chanter N, Sutcliffe IC.Streptococcus equi and Streptococcus zooepidemicus are major etiological agents of upper and lower airway disease in horses. Despite the considerable animal suffering and economic burden associated with these diseases, the factors that contribute to the virulence of these equine pathogens have not been extensively investigated. Here we demonstrate the presence of a homologue of the Streptococcus pneumoniae PsaA protein in both of these equine pathogens. Inhibition of signal peptide processing by the antibiotic globomycin confirmed the lipoprotein nature of the mature proteins, and surface expo...
Semotok CA, Johnson WH, LaMarre J, Gentry PA.This study was designed to evaluate the amounts of coagulation factors and to determine whether the protein profile in pre-ovulatory ovarian follicular fluid aspirated from ovaries collected from mares at slaughter are representative of that in follicular fluid collected from live animals. The proteins evaluated included, (i) albumin, ceruloplasmin and fibronectin, (ii) the procoagulant plasma proteins, Factor V (FV), Factor VII (FVII), Factor X (FX) and prothrombin, and (iii) the anticoagulant plasma proteins, antithrombin and alpha2-macroglobulin. The amounts of the individual proteins were ...
Molenkamp R, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the prototype arterivirus, is an enveloped plus-strand RNA virus with a genome of approximately 13 kb. Based on similarities in genome organization and protein expression, the arteriviruses have recently been grouped together with the coronaviruses and toroviruses in the newly established order Nidovirales. Previously, we reported the construction of pEDI, a full-length cDNA copy of EAV DI-b, a natural defective interfering (DI) RNA of 5.6 kb (R. Molenkamp et al., J. Virol. 74:3156-3165, 2000). EDI RNA consists of three noncontiguous parts of the EAV genome fused ...
Forsell PK, Lindberg A, Karlsson S, Lindgren JA, Claesson HE.It has been demonstrated that equine neutrophils, but not eosinophils, require exogenous arachidonic acid for calcium ionophore A23187-induced leukotriene synthesis. Because cytosolic phospholipase A(2) (cPLA(2)) plays an essential role in leukotriene formation in leukocytes, we investigated the presence of a functional cPLA(2) in equine neutrophils. To determine whether cPLA(2) from neutrophils was catalytically active, we purified the enzyme >6,500 fold with 3% recovery from equine neutrophils. The full-length cDNA sequence encoded a 749-amino acid protein. The deduced amino acid sequence...
Viitanen M, Bird J, Maisi P, Smith R, Tulamo RM, May S.As a prerequisite for the identification of navicular disease markers, the concentrations of cartilage oligomeric matrix protein (COMP), total glycosaminoglycans (GAG), hyaluronan, metalloproteinases (MMP) 2 and 9 and total protein were measured in synovial fluid samples obtained from the distal interphalangeal joint (DIP), the metacarpophalangeal joint (MCP) and the navicular bursa of 24 horses. Mean GAG, COMP and total protein levels were significantly higher in the DIP joint and in the navicular bursa compared to the MCP joint. Hyaluronan content was lower. MMP -2 activity was present in al...
Töneke K.The density and subtype pattern of beta-adrenoceptors in equine tracheal epithelium, tracheal smooth muscle and heart from 6-9 horses were investigated by radioligand binding studies using the nonselective beta-adrenoceptor antagonist 125I-cyanopindolol (ICYP). The specific binding of ICYP was 341 +/- 162 fmol/mg protein (mean +/- SD) for epithelium, 42 +/- 13 fmol/mg for smooth muscle and 124 +/- 39 and 101+/- 19 fmol/mg for the cardiac atrium and ventricle, respectively. The Kd value of ICYP was 6.7 10.2 pmol/L. In competition studies, different concentrations of either the beta2-selective d...
Tkachenko AG, Winston GW.Preincubation of horse liver alcohol dehydrogenase (HLADH) with the oxidative agent, tert-butyl hydroperoxide (tBOOH) results in a twofold stimulation of the ethanol dehydrogenase activity of this enzyme. This stimulation was dependent on tBOOH concentration up to 100 mM; above this concentration tBOOH did not further stimulate ethanol oxidation by HLADH. Active-site-directed reagents and classical ADH binary complexes were used to probe the possible mechanism of this activating effect. The rate and extent of stimulation by tBOOH is strongly reduced by binary complexes with NAD(+) or NADH, who...
Törneke MK, Ingvast-Larsson JC, Johansson JM, Appelgren LE.To determine pharmacokinetics of terbutaline in healthy horses and to relate serum terbutaline concentrations with the drug's pharmacodynamic effects. Methods: 6 healthy horses. Methods: Horses were given terbutaline i.v. (10 microg/kg of body weight) and, 1 week later, p.o. (100 microg/kg). Responses to drug administration (eg, heart rate and serum lactate concentration) were measured. Serum terbutaline concentration was measured by means of gas chromatography with mass spectrometry. Protein binding was determined in vitro. Results: Following i.v. administration, median maximum serum terbutal...
Myshkin AE, Khromova VS.Histidin has been shown to effectively inhibit coagulation of horse oxyhemoglobin (HbO(2)) modified by mercury(II) ion bound to reactive thiol groups of protein. Kinetic parameters were measured and the histidin-to-mercury binding constant was kinetically estimated. Histidin, as other pharmaceutically acceptable compounds with some mercury-binding capacity, has been suggested to alleviate mercury intoxication conditions.
Retamal C, Urzúa J, Alves EW, López ML.It has been suggested that proteins produced in specific regions of the epididymis, mostly androgen dependent glycoproteins, are involved in the sperm maturation process. In the present work, the glycoconjugated distribution pattern and the electrophoretic characteristics of the stallion epididymal proteins were examined using lectin probes. The identification in the luminal fluid of some new proteins, probably synthesized and secreted by the epididymis, is an important initial step to investigate their interaction with the stallion sperm membrane. The binding of FITC-lectins (ConA, WGA, LPA, ...
Watson ED, Thomson SR, Howie AF.A steroidogenic acute regulatory (StAR) protein has been identified in several species as a probable important rate-limiting step in steroidogenesis. This protein is believed to be responsible for transporting cholesterol from the outer to the inner mitochondrial membrane. It is known that equine chorionic gonadotrophin (eCG) stimulates steroidogenesis in the corpora lutea of early pregnant mares and that eCG also upregulates StAR mRNA in bovine ovaries. In the present study, ovarian tissue from cyclic and early pregnant mares was immunostained to detect the distribution of the StAR protein. W...
Blanch EW, Morozova-Roche LA, Hecht L, Noppe W, Barron LD.Vibrational Raman optical activity (ROA) spectra of the calcium-binding lysozyme from equine milk in native and nonnative states are measured and compared with those of the homologous proteins hen egg white lysozyme and bovine alpha-lactalbumin. The ROA spectrum of holo equine lysozyme at pH 4.6 and 22 degrees C closely resembles that of hen lysozyme in regions sensitive to backbone and side chain conformations, indicating similarity of the overall secondary and tertiary structures. However, the intensity of a strong positive ROA band at approximately 1340 cm(-1), which is assigned to a hydrat...
Galeano R, Germanà A, Abbate F, Calvo D, Naves FJ, Hidaka H, Germanà G, Vega JA.Neurocalcin (NC) is a recently characterized EF-hand calcium-binding protein present in a discrete population of sensory neurons and their peripheral mechanoreceptors, but its presence in peripheral nervous system neurons other than in the rat is still unknown. The present study was designed to investigate the occurrence of NC in the dorsal root ganglia (DRG) of several mammalian species (horse, buffalo, cow, sheep, pig, dog, and rat), including humans. DRG were fixed, embedded in paraffin, and processed for immunohistochemistry using a polyclonal antibody against NC. The size of the immunorea...
Richardson DW, Dodge GR.To determine the effects of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) on expression and regulation of several matrix-related genes by equine articular chondrocytes. Methods: Articular cartilage harvested from grossly normal joints of 8 foals, 6 yearling horses, and 8 adult horses. Methods: Chondrocytes maintained in suspension cultures were treated with various doses of human recombinant IL-1beta or TNF-alpha. Northern blots of total RNA from untreated and treated chondrocytes were probed with equine complementary DNA (cDNA) probes for cartilage matrix-related ge...
Chanter N, Talbot NC, Newton JR, Hewson D, Verheyen K.The M-protein genes of Streptococcus equi isolated from 17 outwardly healthy horses after 4 strangles outbreaks had ended, including a quarantined animal, were compared with those of S. equi isolates from 167 active cases of strangles across 4 countries. The healthy horses included 16 persistent S. equi carriers, at least one from each of the four outbreaks. These carriers, despite being outwardly healthy, had empyema of the guttural pouch(es), an enlargement of the equine Eustachian tube. A persistent carrier from two of these outbreaks, the quarantined animal and a healthy animal with normal...
Kobayashi T, Ikeguchi M, Sugai S.The molten globule structure of equine beta-lactoglobulin has been inferred from the hydrogen exchange protection of the backbone amide protons. In order to make it possible to measure the hydrogen exchange kinetics of the individual backbone amide protons, the uniformly (15)N-labeled recombinant protein was expressed in Escherichia coli and the NMR peak assignment was obtained for most of the backbone protons. The chemical shift and NOE results obtained under the condition where the protein assumes the native structure are fully consistent with the known secondary structure of bovine beta-lac...
Herrler A, Pell JM, Allen WR, Beier HM, Stewart F.Insulin-like growth factor-I (IGF-I) promotes early embryonic development in several species. In the rabbit, IGF-I binds to the embryonic coats from Day 3 of development onward by a 38-kDa protein that is probably insulin-like growth factor-binding protein 3 (IGFBP3). In the present study, ligand, Western, and Northern blot analyses were used to demonstrate the presence of IGF-I-binding activity, several immunoreactive IGFBP3 proteins, and IGFBP3 mRNA in horse conceptuses with particularly large amounts of immunoreactive IGFBP3 in the conceptus capsule. In addition, immunoprecipitation of radi...
Fouchécourt S, Métayer S, Locatelli A, Dacheux F, Dacheux JL.Proteins present in and secreted into the lumen of various regions of the stallion epididymis were characterized qualitatively and quantitatively by two-dimensional electrophoresis. Using this proteomic approach, 201 proteins were found in the lumen and 117 were found that were secreted by the epithelium in various parts of the organ. Eighteen proteins made up 92.6% of the total epididymal secretory activity, lactoferrin (41.2%) and clusterin (24.8%) being the most abundant. Procathepsin D, HE1/CTP (cholesterol transfer protein), GPX (glutathione peroxidase), beta-N-acetyl-hexosaminidase, and ...
Green MK, Johnston MV, Larsen BS.To elucidate the role of high mass accuracy in mass spectrometric peptide mapping and database searching, selected proteins were subjected to tryptic digestion and the resulting mixtures were analyzed by electrospray ionization on a 7 Tesla Fourier transform mass spectrometer with a mass accuracy of 1 ppm. Two extreme cases were examined in detail: equine apomyoglobin, which digested easily and gave very few spurious masses, and bovine alpha-lactalbumin, which under the conditions used, gave many spurious masses. The effectiveness of accurate mass measurements in minimizing false protein match...
Lepczyński A, Ożgo M, Dratwa-Chałupnik A, Robak P, Pyć A, Zaborski D, Herosimczyk A.The main objectives of the study were to: (1) deeply analyse the serum protein composition of Equus caballus, (2) assess the effectiveness of the high-abundant protein depletion and improve the concentration of medium- and low-abundant proteins. The analysis were performed on the blood plasma of three healthy part-Arabian mares. The implementation of two-dimensional electrophoresis and matrix-assisted laser desorption/ionisation - time of flight mass spectrometry allowed us to establish a horse plasma proteome map. Serum proteins were resolved at pH 4 to 7, followed by 12% SDS-PAGE. As a resul...
Nürnberger S, Rentenberger C, Thiel K, Schädl B, Grunwald I, Ponomarev I, Marlovits S, Meyer C, Barnewitz D.The present study reports for the first time the presence of giant crystals in mitochondria of equine chondrocytes. These structures show dark contrast in TEM images as well as a granular substructure of regularly aligned 1-2 nm small units. Different zone axes of the crystalline structure were analysed by means of Fourier transformation of lattice-resolution TEM images proving the crystalline nature of the structure. Elemental analysis reveals a high content of nitrogen referring to protein. The outer shape of the crystals is geometrical with an up to hexagonal profile in cross sections. It ...
Matsumura Y, Li J, Ikeguchi M, Kihara H.Acidic buffer conditions are known to stabilize helix-rich states of even those proteins with a predominantly beta-sheet native secondary structure. Here we investigated whether such states also exist under alkaline buffer conditions. The guanidine hydrochloride (GuHCl)-induced unfolding transition and kinetic refolding of equine beta-lactoglobulin (ELG) by GuHCl-jump were investigated at pH 8.7 by far-ultraviolet circular dichroism. We found that an equilibrium intermediate appeared in 45% ethylene glycol (EGOH) buffer with 1.5 M GuHCl. The intermediate is rich in non-native alpha-helix, whic...
Miksovská J, Day JH, Larsen RW.Carbon monoxide binding to myoglobin was characterized using the photothermal beam deflection method. The volume and enthalpy changes coupled to CO dissociation were found to be 9.3+/-0.8 mL x mol(-1) and 7.4+/-2.8 kcal x mol(-1), respectively. The corresponding values observed for CO rebinding have the same magnitude but opposite sign: Delta V=-8.6+/-0.9 mL x mol(-1) and Delta H=-5.8+/-2.9 kcal x mol(-1). Ligand rebinding occurs as a single conformational step with a rate constant of 5 x 10(5) M(-1) s(-1) and with activation enthalpy of 7.1+/-0.8 kcal x mol(-1) and activation entropy of -22.4...
Piquette GN, Kenney RM, Sertich PL, Yamoto M, Hsueh AJ.The association of equine granulosa-theca cell tumors with atrophied contralateral ovaries and abnormal estrous cycles suggests that these tumors produce hormones that affect pituitary gonadotropin production. Because inhibin, a heterodimer protein secreted by granulosa cells, decreases FSH production, we examined the presence of inhibin alpha- and beta A-subunits and their mRNAs in ovarian tumors obtained from three mares. These tumors contained neoplastic cords and nodules, multiple fluid-filled cysts, and a predominance of neoplastic granulosa cells. Reduced proteins from tumor-conditioned ...
Ueda H, Abe M, Takehana K, Iwasa K, Hiraga T.The innervation of the red pulp in the spleen of horse and pig was investigated by electron microscopy. In addition, the neurilemma was studied by immunohistochemistry specific for S-100 protein. In the pig, a large population of smooth-muscle cells extending from the smooth-muscle trabeculae was present in the red pulp. The cytoplasmic processes of reticular cells enwrapped the smooth-muscle cells, and nerve fibres were distributed between the smooth-muscle cells and the reticular cells. The nerve terminals clustered toward the facing of the smooth-muscle cells. Nerve fibres and terminals wer...
Takeda S, Ohta M, Ebina S, Nagayama K.Horse L-ferritin cDNA was cloned from horse liver, and the base sequence was determined. The L-ferritin was expressed using pTZ18U encoding lac promoter, and found to possess an additional 8-amino acid sequence at the N-terminus as compared with commercially obtained horse spleen (natural) ferritin. It was determined that there was Pro at position 94 in both the recombinant and natural L-ferritin, although it was previously reported that Leu was in this position in the natural species. Transmission electron microscopy showed that this recombinant ferritin formed a 24-mer shell.
McCoy AM, Arrington J, Yau PM.The protein content of amnion is thought to be the primary contributor to its efficacy as a biological dressing for wounds. Protein elution into antibiotic processing media has been reported, but the effect of antiseptic-based processing methods is unknown. Amniotic membranes were collected from eight healthy mares. Samples were collected after removal of gross debris. Tissues were subsequently divided and processed with either 0.05% chlorhexidine or 2% iodine/0.25% acetic acid. After protein extraction and trypsin digestion, the proteins were labeled with 8-plex iTRAQ tags, combined, and anal...
Turner RM, Casas-Dolz R, Schlingmann KL, Hameed S.To determine whether a homologue of A-kinase anchor protein 4 (AKAP4) is present and functional as an AKAP in equine spermatozoa and examine the effect of semen cooling and cryopreservation on binding of equine AKAP4 to the regulatory (RII) subunit of protein kinase-A (PK-A). Methods: Ejaculated semen collected from 2 fertile stallions, 3 bulls, and 3 humans. Methods: Identification of an equine homologue of AKAP4 was investigated via DNA sequencing. Protein was extracted from the spermatozoa of each species for immunoblot analysis to identify AKAP4 and its precursor protein, pro-AKAP4; immuno...
Sartori C, Guzzo N, Normando S, Bailoni L, Mantovani R.The present work is aimed at evaluating the behaviour of Italian Heavy Draught Horse (IHDH) foals reared in semi-covered stables and fed two isoenergetic total mixed rations with different dietary protein levels (13.2% and 10.6% of CP on dry matter). The study was prompted by the restrictions for nitrate emissions in farms of the European Nitrate Directive. One suggested solution is to reduce dietary protein while maintaining normal performance and welfare, but there is a lack of literature in studies of horses. The behaviours of 20 foals of 437±60 kg of BW, aged 379±37 days and stabled in f...
Higgins AJ, Lees P.The presence of cyclooxygenase products of arachidonic acid metabolism in carrageenin-induced inflammatory exudate was investigated in ponies using two models. In the first model, an inflammatory response was stimulated by injecting carrageenin into subcutaneously implanted polypropylene tissue cages and exudates were collected at five predetermined times between 3 and 48 h. In the second model, exudates were harvested at 6, 12 and 24 h from carrageenin-impregnated polyester sponges which had also been inserted beneath the skin. Prostaglandin (PG) E2, thromboxane (TX) B2 and the stable breakdo...
Jones AJ, Bee JA.The digital flexor tendons of the neonate and adult horse have been compared with respect to variation in extracellular matrix composition along their length. Two pepsin-sensitive, acetic acid soluble proteins, molecular weight (Mr) 52 kD (np 52) and Mr 54 kD (np 54), were prominent throughout the length of neonatal tendons. In adult tendon, np 52 and np 54 were less abundant and restricted to the cannon (metacarpal) region. In contrast, a single pepsin- and collagenase-resistant protein of Mr 55 kD (fp 55) was exclusive to the fetlock (metacarpophalangeal joint) region regardless of age, alth...
Hurcombe SD, Matthews AL, Scott VH, Williams JM, Kohn CW, Toribio RE.To determine the predictive value of serum concentrations of total protein (sTP), albumin (sAlb), and globulin (sGlob) measured by automated calorimetric assays to estimate serum immunoglobulin G (sIgG) concentrations in neonatal foals and identify failure of transfer of passive immunity when compared to turbidoimmunometric assay determinations of sIgG. Methods: Retrospective and prospective analysis of laboratory data. Methods: University tertiary care facility. Methods: Group 1 (retrospective): foals (n = 45) ≤7 days of age in which sIgG, sGlob, sAlb, and sTP concentrations were measured o...
Guerra-Shinohara EM, Barretto OC.Erythrocyte membrane proteins from 44 representative mammals were studied. Protein 4.2 was not detected in guinea pigs (Cavia porcellus) (N = 14), Southern Brazilian swamp large rats (Myocastor coypus) (N = 2), cutias (Dasyprocta sp) (N = 4), and horses (Equus caballus) (N = 13). These animals also presented high ankyrin concentrations except for the horse which did not exhibit a sharp band, although minor components located between proteins 2 and 3 could account for the ankyrin family. The rodents studied did present band 6, which was not detectable in other common rodents such as white rats ...
Badinga L, Michel FJ, Fields MJ, Sharp DC, Simmen RC.Uterine expression of the mRNA encoding antileukoproteinase (ALP) is highest in pig uterus during mid- to late pregnancy, suggesting a stage of pregnancy-dependent role for this elastase/cathepsin G protease inhibitor in feto-maternal interactions. To examine a potential relationship between uterine synthesis of ALP and the type of placentation in mammalian species, the expression of ALP mRNA and/or protein in pregnant mares, cows, rats, and mice was evaluated. Genomic DNA and mRNA hybridization analyses were performed using a porcine ALP cDNA as probe. The concentration of ALP protein in repr...
De Ceulaer K, Delesalle C, Van Elzen R, Van Brantegem L, Weyns A, Van Ginneken C.Intestinal strangulation often leads to enterectomy after which ileus can develop. This has prompted research to look into possible pathophysiological processes triggering equine ileus. However, morphological changes of the small intestinal smooth muscle in relation to equine colic have not yet been studied. Objective: The presence of some smooth muscle proteins was morphologically assessed and quantified in control and colic horses. In addition, the up- or down-regulation of heat shock proteins (HSP20 and HSP27) influencing the contractility of smooth muscles was studied. Methods: Cranial res...
Steinbach F, Mauel S, Beier I.Interferons (IFNs) are important mediators of the immune system. Their antiviral activity is an integral part of the innate immune defence, but all IFNs have immune regulatory functions also. Besides rec.eq.IFN-beta detailed descriptions on other rec.IFNs were lacking and none of the proteins was available. To compare the equine IFNs and allow detailed studies on proteins and bioactivity, we performed the expression cloning of rec.eq.IFN-alpha, -beta and -gamma. To achieve maximal expression, a bacterial expression system was chosen. Additionally, rec.eq.IFN-beta and -gamma were expressed in m...
Milner PI, Smith HC, Robinson R, Wilkins RJ, Gibson JS.Hypoxia and acidosis are recognized features of inflammatory arthroses. This study describes the effects of IGF-1 and TGF-β(1) on pH regulatory mechanisms in articular cartilage under hypoxic conditions. Acid efflux, reactive oxygen species (ROS), and mitochondrial membrane potential were measured in equine articular chondrocytes isolated in the presence of serum (10% fetal calf serum), IGF-1 (1, 10, 50, 100 ng/ml) or TGF-β(1) (0.1, 1, 10 ng/ml) and then exposed to a short-term (3 h) hypoxic insult (1% O(2)). Serum and 100 ng/ml IGF-1 but not TGF-β(1) attenuated hypoxic regulation of pH hom...
Lancheros-Buitrago J, Rodriguez-Villamil P, Gregory J, Bastos H, Camacho CA, Caballeros JE, Cazales N, Barros E, José de Jesus Silva M, Pimentel A....Characterization of the uterine proteome before the entry of the conceptus to the uterus is essential to know the factors involved in the physiological events of gestation. The objective of the study was to compare proteomic profile of uterine fluid collected on day 5 post ovulation of cyclic and inseminated mares. Samples of endometrial secretion were recovered over 2 cycles during the fifth day post ovulation. The first cycle constituted the Cyclic group and in the following cycle, the same mares were inseminated and considered as the Inseminated group. All the samples were subjected to two-...
Longland AC, Barfoot C, Harris PA.The effects of different water-soaking treatments on removal of water-soluble carbohydrates (WSC), WSC constituents and protein from four UK hays were determined. Hays were soaked in water for up to 16 hours at mean temperatures of 8°C, 16°C, in hot tap water (initially 49°C) or agitated and rinsed in clean water at 16°C. Initial hay WSC contents ranged from 154 to 216 g/kg dry matter. Losses of WSC from hays after 16 hours soaking at 8°C, 16°C, 16°C plus agitation and 49°C averaged 28, 46, 49 and 44 per cent, respectively. Corresponding percentage losses of fructan were 16, 37, 39 and...
Malark JA, Nixon AJ, Skinner KL, Mohammed H.Physical, biochemical, and cytologic properties of synovial fluid from digital flexor tendon sheaths of clinically normal horses were investigated. Tendon sheath fluid was pale yellow, clear, and did not clot. Volume of fluid within a tendon sheath varied minimally, with a mean of 2.11 ml. Total erythrocyte counts were higher than values observed in normal equine joint fluid, whereas values for total leukocyte count (770 +/- 73 cells/mm3), viscosity (6.05 +/- 0.58 cs), and protein concentration (7.87 +/- 0.03 mg/ml) were similar to those in joint fluid. Large mononuclear cells were the predomi...
Hwang HJ, Han JW, Jeon H, Han JW.Lectin is an important protein in medical and pharmacological applications. Impurities in lectin derived from natural sources and the generation of inactive proteins by recombinant technology are major obstacles for the use of lectins. Expressing recombinant lectin with a tandem repeat structure can potentially overcome these problems, but few studies have systematically examined this possibility. This was investigated in the present study using three distinct forms of recombinant mannose-binding lectin from (BPL2)-i.e., the monomer (rD1BPL2), as well as the dimer (rD2BPL2), and tetramer (rD4...
Dyson DH, Pascoe PJ.A controlled study of the cardiovascular responses in horses anesthetized with acepromazine (0.05 mg/kg of body weight, IV), guaifenesin (100 mg/kg, IV), thiamylal (5.0 mg/kg, IV), and halothane in O2 (1.2 to 1.4% end-expired concentration) was performed to determine whether hypotension could be prevented by use of various treatments. Six horses were given 5 treatments in a randomized sequence: no treatment (control), methoxamine (0.04 mg/kg, IV), lactated Ringer solution (20.0 ml/kg, IV), 7.5% hypertonic saline solution (4.0 ml/kg, IV), or constant infusion of dobutamine (5.0 mg/kg/min, IV) d...
Kankavi O, Ata A, Akif Ciftcioglu M.The presence of surface-active material in the lung alveolus has been known for several decades as being essential for normal lung function. The host defense and controlling inflammatory processes of the lung are the major functions of SP-A and SP-D. SP-A and SP-D were originally demonstrated in alveolar type II cells, but recent studies have shown extrapulmonary expression of SP-A and SP-D indicating systemic roles of these proteins. Present study describes the presence of SP-A and SP-D in the stallion genital tract, prepuce, prostate, testis, and seminal vesicle using Western blotting and im...
Combie JD, Nugent TE, Tobin T.Morphine could be detected in horses dosed with 0.1 mg of drug/kg of body weight for up to 48 hours in blood and 144 hours in urine. This dose of morphine elicited no observable effects and is a suggested analgesic dose. Computer analysis revealed that a 3-compartment open system was the best fitting model with a serum half life (t1/2(beta)) of 87.9 minutes and a urine t1/2(beta) of 101.1 minutes. Binding to equine serum proteins was linear over a drug concentration range of 3.88 X 10(-5)M to 3.50 X 10(-8)M and averaged 31.6%. In RBC-partitioning experiments, 78.1% of the drug was found in the...
Li CH, Ng TB, Yamashiro D, Chung D, Hammonds RG, Tseng LF.Beta-endorphin has been isolated from equine pituitaries. Its amino acid sequence is identical to that of ovine, bovine and camel beta-endorphins except for substitution of the threonine residue at position 6 by serine. The equine beta-endorphin has also been synthesized by the solid-phase method. In comparison with the human hormone, equine beta-endorphin was shown to possess 3 times the receptor-binding activity in rat membrane preparations and 1.6 times the analgesic potency in the mouse tail-flick assay.
Juillerat MA, Taniuchi H.To investigate the role of evolutionarily invariant leucine 32 of horse cytochrome c, analogs of residues 28-38, (28-38), each containing a substituted amino acid at positions 32 or 35 were synthesized using Merrifield's method. Position 35 is leucine in horse cytochrome c but replaced by nonpolar amino acids in some species. The ability of the analogs to bind to the two-fragment complex of ferri- or ferro heme fragment (1-25)H and apofragment (39-104) was measured using gel filtration and equilibrium dialysis. Replacement of leucine 32 with isoleucine, for example, increased the dissociation ...
Júnior WHF, Garcia de Carvalho JR, Mendes de Almeida ML, Macedo Lemos EG, Brioschi Soares OA, Ribeiro G, de Queiroz-Neto A, de Camargo Ferraz G.We compare the expression levels of the lactate transporter complex consisting of the lactate transporter, monocarboxylate transporter 1 (MCT1), and its ancillary protein, cluster of differentiation 147 (CD147), in the membranes of red blood cells (RBCs) from two breeds of jumping horses and associate the expression levels of these proteins with their jumping ability. The expression levels of MCT1 and CD147 proteins on the membranes of RBCs collected from 30 show jumping horses of two different breeds were quantified: the Brazilian Sport Horses (n = 17) and the European Warmbloods (n = 13). ...
Brooks AC, Menzies-Gow NJ, Wheeler-Jones CP, Bailey SR, Elliott J, Cunningham FM.Lipopolysaccharide (LPS) can activate equine platelets directly or indirectly, via leukocyte-derived platelet activating factor (PAF). Thromboxane (Tx) production by LPS-stimulated equine platelets requires p38 MAPK and this kinase has been suggested as a therapeutic target in endotoxaemia. The present study has utilised selective inhibitors to investigate the role of p38 MAPK and two other kinases, phosphatidylinositol-3 kinase (PI3K) and protein kinase C (PKC), in regulating PAF-induced Tx production, aggregation and 5-HT release in equine platelets, and the modification of these responses b...
