The study of cells in horses encompasses the examination of various cell types and their functions within the equine body. Cells are the basic structural and functional units of life, and in horses, they contribute to numerous physiological processes, including growth, repair, and immune responses. Different cell types, such as red blood cells, white blood cells, and muscle cells, each perform specific roles that are vital for maintaining the health and homeostasis of the horse. This topic includes research on cellular mechanisms, cellular responses to disease or injury, and the application of cellular biology in equine medicine. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and significance of cells in equine biology and health.
Wilks CR.The immune response in horses following experimental infection with equine herpesvirus type 1 (EHV-1) was assessed by measuring cytotoxicity for EHV-1-infected target cells. A technique was developed, using [125I]5-iodo-2'-deoxyuridine ([125I]IUDR)-labeled equine fetal kidney cells infected with EHV-1 as the target cells. It was shown that peripheral blood leukocytes from a recovered horse were capable of lysing target cells, as measured by the loss of radio-active label. Following the experimental infection of specific-pathogen-free ponies with EHV-1, cytotoxicity was obtained with fresh auto...
Weiland F, Matheka HD, Coggins L, Hatner D.Morphological studies of EIAV reveal knobs on the surface of the particles, conically and tubularly shaped cores, budding particles with dense crescents directly underlying the plasma membrane, and distinct intracytoplasmic structures in infected cells.
Gilmour JS, Mould DL.Plasma, serum and cells were prepared from blood taken from acute cases of grass sickness, and plasma was fractionated by gel filtration and salt precipatation. These preparations were all tested for neurotoxic activity by injection into ponies. Plasma and serum were found to produce the neurohistological changes seen in grass sickness, as was a plasma protein fraction of molecular weight 30,000 or greater. Activity was retained following storage at--75 degrees C for 15 months. Plasma given orally to a pony produced no detectable effect, nor was activity demonstrated following the injection of...
Yu DT, Gale RP, Kacena A, Pearson CM.Rosette formation between human lymphocytes and horse red blood cells could be promoted by a low pH medium, overnight incubation and a temperature of 4 degrees C. The percent of sheep, horse and human rosette-forming cells in the peripheral blood were 71.7 +/- 1.8, 30.5 +/- 2.8 and 28.3 +/- 3.4 respectively. However, their percentages in thymuses were 97.1 +/- 1.1, 91.4 +/- 2.4 and 89.0 +/- 3.4. Using preparations of isolated subpopulations, it was observed that the horse and human red cell rosette-forming cells were probably also "early" sheep red cell rosette-forming cells. Rosette formation...
Kitchell RL, Stromberg MW, Davis LH.Quantitative studies were made of cells in the dorsal motor nucleus of the vagus nerve in the horse, dog, cat, pig, sheep, goat, and calf. This nucleus was larger in ruminants than in nonruminants. Some cells in all parts of the nucleus supplied visceral structures in the head, cervical, thoracic, and abdominal regions; however, a definite topographic localization did exist within the nucleus. Eighty percent of the cells which supplied the abdominal viscera were in the rostral and rostral-middle regions. The cells which supplied the thoracic viscera were distributed almost equally within the r...
Thouless ME, Bryden AS, Flewett TH, Woode GN, Bridger JC, Snodgrass DR, Herring JA.Human, piglet, mouse, foal, lamb, calf and rabbit rotaviruses all infected, but could not readily be subcultured in LLC MK2 cells. Cells infected with mouse and calf rotaviruses reacted by indirect immunofluorescence (FA) with convalescent serum from children, piglets, mice, foals, lambs, calves or rabbits, taken after rotavirus infection. Human, calf, piglet, mouse and foal rotaviruses reacted with human, calf, mouse, foal and lamb convalescent serum by complement fixation (CF). It was not possible to distinguish between different rotaviruses by CF or FA. Neutralization tests, however, detect...
Samuel CA, Allen WR, Steven DH.In early pregnancy the equine placenta consists of a simple apposition of fetal and maternal epithelia, but it becomes more complex with the formation of microcotyledons between 75 and 100 days of gestation. Although the placental barrier maintains an epitheliochorial arrangement throughout the course of pregnancy, a thinning of the maternal epithelium and a progressive indentation of the chorionic epithelium by fetal capillaries shortens the length of the diffusion pathway and reduces the amount of placental tissue between fetal and maternal bloodstreams. These structural modifications may re...
Helmstaedter V, Feurle GE, Forssmann WG.Equine pancreas was investigated with immunohistochemical methods to study the distribution of endocrine cells immunoreactive to anti-insulin, anti-glucagon, and anti-somatostatin. A-cells demonstrable by anti-glucagon are located in the center of Langerhans islets and frequently in the duct epithelium. Few A-cells are seen associated to acini. Anti-insulin reactive B-cells form a large zone around the center of the Langerhans islets in which some B-cells lie between exocrine cells and others, although few, are located in the duct epithelium. D-cells stained with anti-somatostatin serum form a...
Kramer JW, Nickels FA, Bell T.Examination of effusions from body cavities must include a search for neoplastic as well as inflammatory cells. Neoplastic cells found in the thorax are generally derived from adenocarcinomas or mesotheliomas. Mesotheliomas are relatively uncommon and the neoplastic cells found in effusions are difficult to differentiate from activated cells in inflammatory effusions. An ante-mortem diagnosis of mesothelioma was made in a mare on the basis of the large volume of fluid produced, the pleomorphic mesothelial cells, the polyp formation and the absence of PAS staining material after digestion of th...
Groman EV, Schultz RM, Engel LL, Orr JC.In the reduction of 17beta-hydroxy-5alpha-androstan-3-one to the 3beta-alcohol, horse liver alcohol dehydrogenase utilizes the 4-pro-R hydrogen of NADH whereas the 3(17)beta-hydroxysteroid dehydrogenase of Pseudomonas testosteroni utulized the 4-pro-S hydrogen. These observations provide an exception to the rule proposed by Alworth and Bentley that with regard to the paired methylene hydrogens at C-4 of NADH and NADPH "the stereospecificity of a particular reaction is fixed and does not vary with the source of the enzyme preparation". It is also apparent that for these two enzymes, the selecti...
Moorthy AR, Spradbrow PB.Mycoplasmas were isolated from two of 43 nasal swabs taken from live horses, and from one of 28 tracheal swabs taken from slaughtered horses. The slaughtered horse that yielded mycoplasmas had no gross pathological changes in the respiratory tract, but the nasal isolations were made from horses with rhinitis. The three mycoplasmas could be distinguished by cultural characteristics, and probably they represent three different species.
Forssmann A.The islets of Langerhans of the equine pancreas were examined with the electron microscope after immersion or perfusion fixation. Five cell types could be distinguished after fixation by either technique: 1. A-cells, situated at the center of the islets, 2. B-cells, containing mostly "pale granules" and constituting the principal cell type of the periphery of the islets, 3. D-cells, also located mainly at the periphery of the islets, 4. G-cells, found at the edge of the islets and in the exocrine pancreas, and 5. S-cells, (small granule cells), which are relatively few in number and occur only...
Dubin A, Koj A, Chudzik J.Cytoplasmic granules were isolated from horse blood polymorphonuclear leucocytes by the heparin method and extracted with 0.9% NaCl by repeated freezing. Soluble proteins were separated on a column of Sephadex G-75 followed by chromatography on a column of CM-Sephadex with a NaCl gradient. Gel filtration, density-gradient centrifugation, isoelectric focusing and 0.1% sodium dodecyl sulphate/polyacrylamide-gel electrophoresis at pH 7.0 and at pH 4.5 were used to determine molecular parameters of proteinases. Three enzymes hydrolysing both casein and N-benzyloxycarbonyl-L-alanine nitrophenyl est...
Wetz K, Crichton RR.In apoferritin, but not in ferritin, 1.0 +/- 0.1 cysteine residue per subunit can be modified. In ferritin 3.3 +/- 0.3 lysine residues and 7.1 +/- 0.7 carboxyl groups per subunit can be modified, whilst the corresponding values for apoferritin are 4.4 +/- 0.4 lysine residues and 11.0 +/- 0.4 carboxyl groups per subunit. Modification of lysine residues which maleic anhydride and carboxyl groups with glycineamide in apoferritin which has been dissociated and denatured in guanidine hydrochloride leads to the introduction of 9.1 +/- 0.5 maleyl groups per subunit and 22.0 +/- 0.9 glycineamide resid...
Sells DM, Hildebrandt PK, Lewis GE, Nyindo MB, Ristic M.The ultrastructure of the etiological agent of equine ehrlichiosis, Ehrlichia equi, was studied in equine peripheral leukocytes. The organisms occurred within membrane-lined cytoplasmic vacuoles of neutrophils and eosinophils. Ovoid, round, and rod-shaped profiles were observed. From 1 to 33 organisms were present in a thin-section profile of a cytoplasmic vacuole. Many cells contained multiple organism-containing vacuoles. The organisms had a cell wall and plasma membrane, and internally they consisted of electron-dense and lucid areas. A great variation in size was observed. The morphologica...
Heyneman RA, Bruyninckx WJ, Vercauteren RE.Two distinct groups of acid phosphatase containing granules were characterized in neutrophils, each group displaying different multiple forms of the enzyme. The heavy granule acid phosphatase showed a lysosomal location. A second lighter group of particles contained a thermolabile, thiol-dependent acid p-nitrophenyl and alpha-naphtylphosphatase, an enzyme clearly different from lysosomal acid phosphatase. Acid phosphatase activity from eosinophil leukocytes appeared to be totally associated with the typical eosinophil granules. On mechanical disruption of these particles, an acid phosphatase w...
Rejnö S.LDH is an intracellular enzyme, which when cells degenerate is released to the extracellular spaces and body fluids. Cells and organs in the mammalian body differ from each other with respect to their LDH isoenzyme patterns. These circumstances have led to the use of LDH isoenzyme determinations in laboratory diagnostic work. In the present investigation total LDH activity and LDH isoenzyme distribution in equine synovial fluid from healthy joints, joints with serous arthritis, osteochondrosis dissecans and arthrosis, were determined. The fluids from the diseased joints differed from normal sy...
Johansson HE, Rejnö S.Light and electron microscopic examination was made on equine synovial membrane from 23 healthy joints, nine joints with synovitis caused by intraarticular fracture and 10 joints with synovitis caused by osteochondrosis dissecans. Histologically as well as ultrastructurally the equine synovial membrane from healthy joints was of principally the same character as described in other species. Three types of synovial membrane — areolar, fibrous and adipose — and two types of lining cell were distinguished histologically. Ultrastructurally three types of lining cells were distinguished: A and Î...
Pavelka M, Ronge HR, Stockinger G.Tracheal epithelia of ten different mammals were investigated with the light and the electron microscope. Characteristic differences were found concerning the thickness of the epithelia, the length of the cilia, the density of the cells in the epithelia, the numerical distribution of the different cells and their ultrastructure. Special attention was paid to the morphology of the kinetosomes. Brush cells and chromaffin cells, which are sparsely distributed in the different tracheal epithelia, were discussed.
Stewart M.The structure of vertebrate skeletal muscle is reviewed. The mechanism of muscular contraction and its control is then discussed from the point of view of molecular structure. Contraction takes place by a sliding filament mechanism produced by cross-bridges which form between thick and thin filaments. Control is exercised by tropomyosin and troponin. When the calcium concentration is low, these proteins interfere with the formation of cross-bridges and prevent contraction, but when the calcium concentration is increased, they no longer interfere and contraction proceeds.
Kolthammer J.In vitro studies have shown that uncoated carbon and carbon coated with an acrylic hydrogel are capable of adsorbing drugs from horse serum at 37 degrees. Increase in the coating weight from 2 to 4% decreased the rate of adsorption but not the total capacity. In vivo data supports the concept of carbon haemoperfusion for use in the treatment of drug overdose.
Banks KL.The monocytes of horses infected with equine infectious anemia virus were shown by their failure to migrate from capillary tubes and their increased adherence to erythrocytes to be activated.
Swerczek TW.Small but significant numbers of primary and secondary spermatocytes and spermatids have been observed in the semen of some Thoroughbred stallions. Extensive histological examination of the testes of affected animals has not been undertaken but in one young stallion which died as the result of a leg injury, the premature dehiscence of these cells seemed to be related to segmental defects within the seminiferous tubules. The causes of lesions leading to premature shedding of germ cells are discussed.
Ennulat D, Brown CA, Brown SA.To evaluate the effects of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) on canine and equine mesangial cell (MC) proliferation in vitro. Methods: Third- through eighth-passage canine and equine MC were obtained from explant outgrowth after differential sieving of glomeruli isolated from the kidneys of clinically normal dogs and horses. Methods: Mitogenic effects of serum, insulin, EGF, and PDGF were evaluated in MC by induction of DNA synthesis, measured as stimulation of [3H]thymidine incorporation and increase in cell numbers. Results: Epidermal growth factor was a...
Ochi A, Nishioka T, Kurimoto S, Kishi D, Ueno T, Nukada T.A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8Â cm in diameter, covered the upper left intermediate and corner incisor teeth (nos. 602 and 603 according to the modified Triadan system) and radiographic examination revealed displacement and lysis of the incisors. Histologically, the tumour was composed of a dense proliferation of spindle-shaped cells and neoplastic odontogenic epithelial cells arranged in island, follicular, plexiform or sheetlike patterns. The spindle-shaped cells were immunopositive for cytokeratins AE1/A...
Gable TL, Woods GL.The objectives were to compare cumulus type with nucleus form in equine cumulus oocyte complexes (COCs), to define the percentage of germinal vesicle (GV)-stage oocytes within a population of mares, and to further define GV nucleus shapes of equine oocytes. Cumulus types were as follows: 1) compact (56/208, 26.9%), 2) slightly expanded (37/208, 17.8%), 3) moderately expanded (27/208, 13.0%), 4) greatly expanded (15/208, 7.2%), or 5) denuded (73/208, 35.1%). One hundred thirty of 208 COCs (62.5%) were GV-stage, 21/208 (10.1%) were condensed chromatin-stage, 8/208 (3.8%) were polar body-stage, 4...
Benbarek H, Deby-Dupont G, Caudron I, Deby C, Lamy M, Serteyn D.Divergent results have been reported on the effects of lipopolysaccharides (LPS) on the activation of equine polymorphonuclear leukocytes (PMN). We therefore attempted to determine whether LPS alone can stimulate equine PMN or whether plasma factors are necessary. PMN were isolated from citrated blood on a discontinuous density gradient of Percoll. The luminol (10(-3) mol/L)-enhanced chemiluminescence (CL) of 1.25 x 10(6) cells was measured after addition of Escherichia coli LPS (0.001-10 micrograms/ml) alone or after incubation in autologous plasma (1 h, 37 degrees C). After direct stimulatio...
Flieger S, Sławomirski J, Boratyński Z, Jastrzebski M.Two medullae oblongatae of horses were cut into 15 microns cross-sections and stained according to the modified method of Nissel. The lateral motor nucleus lies in the lateral and median part of the ventral column of spinal cord grey matter. It adjoins medially nucleus motorius medialis of the spinal ventral column. Cells of this nucleus occur both along the whole lumbar and sacral segment of the spinal cord. In the lateral motor nucleus three cell groups are distinguished-median, basal and lateral. The latter is divided in some segments into subgroups-dorsal and ventral. Along the nucleus qui...
Liu IK, Walsh EM, Bernoco M, Cheung AT.Two bronchoalveolar lavages, 24 h apart, were performed on 15 foals, ranging in age from 1 to 21 days. In the first lavage, a numerical deficiency in alveolar macrophages was demonstrated in foals up to 2 weeks of age when compared with older (2-3 years of age) horses. Alveolar macrophages obtained from the lungs of 2-3-day-old foals also demonstrated significant impaired chemotactic function. In the second lavage, although an increase of alveolar macrophages was noted, a dramatic increase of polymorphonuclear neutrophil (PMN) mobilization occurred in the foals, thus providing a phagocytic bac...
Breit S, Stiglhuber A, König HE.Striking synovial structures were taken and their surface was investigated by scanning electron microscopy. Depending where the probes were taken from, the stratum synovial was arranged in a different way. The synovial intima seems to miss under the tendon of the long/commune extensor muscle, the collateral ligaments and the sesamoidean collateral ligaments. That is why the subsynovial tissue forms the superficial layer. The surface of the probes taken sidewards to the tendon of the extensor muscle and of the synovial fold, which is situated between the metacarpus/metatarsus and the proximal p...
Marquardt J, Heymer J, Heinz H, Deegen E, Adolf GR, Leibold W.Interferon is known to induce antiviral mechanisms and to exert immunoregulatory capacities on various cell types. The antiviral capacity of recombinant equine interferon-beta 1 (rEqIFN-beta 1) is most sensitively monitored by indirect quantitation of multiplication of vesicular stomatitis virus (VSV) in blood cells of horses. As few as 0.5 pg rEqIFN-beta 1/ml can be assessed by means of 90% reduction of VSV-replication in whole blood (w.b.) as well as in isolated mononuclear blood cells (MNC) in spite of individual variations. The immunoregulatory influence of 20-50 pg rEqIFN-beta 1/ml is suf...
Hinrichs K, Love CC, Choi YH, Varner DD, Wiggins CN, Reinoehl C.Germinal vesicle (GV)-stage horse oocytes with diffuse chromatin are meiotically incompetent and degenerate in culture, whereas horse oocytes having condensed chromatin within the GV are meiotically competent. Degeneration of incompetent oocytes in culture may be related to premature GV breakdown, which could possibly be prevented by inhibition of m-phase protein activity. We examined the effects of 6-dimethylaminopurine (6-DMAP), butyrolactone and roscovitine on GV-stage horse oocytes. Culture in the presence of 2 mM 6-DMAP for 24 h suppressed meiosis (2% MI or MII compared with 38% for untre...
Hago BE, Plummer JM, Vaughan LC.The structure of equine synovial tendon sheaths and bursae has been examined by light and scanning electron microscopy. Tissue samples were obtained from horses of various types and ages with no clinical evidence of sheath or bursal disorders. The interior of both structures was lined by a cellular layer superimposed on a vascular zone supported by a fibrous layer. The pattern of cell distribution of the lining varied from site to site within the same structure depending on the nature of the underlying tissue and on the amount of movement to which the structure was subjected. The cellular laye...
Umair M, Scheeren VFDC, Beitsma MM, Colleoni S, Galli C, Lazzari G, de Ruijter-Villani M, Stout TAE, Claes A.In vitro production (IVP) of equine embryos is increasingly popular in clinical practice but suffers from higher incidences of early embryonic loss and monozygotic twin development than transfer of in vivo derived (IVD) embryos. Early embryo development is classically characterized by two cell fate decisions: (1) first, trophectoderm (TE) cells differentiate from inner cell mass (ICM); (2) second, the ICM segregates into epiblast (EPI) and primitive endoderm (PE). This study examined the influence of embryo type (IVD versus IVP), developmental stage or speed, and culture environment (in vitro ...
Tunón AM, Rodriguez-Martinez H, Haglund A, Albihn A, Magnusson U, Einarsson S.Cyclical accumulation of uterine fluid occurs during oestrus and is often seen in excessive volumes in mares considered susceptible to endometritis. Since the mechanisms behind the formation of free uterine fluid remain to be clarified, the fine structure of the secretory equine endometrium was studied in biopsies collect during videoendoscopy from 14 endometritis-free, 4-9-year-old mares during oestrus. A distinct oedema of the tunica mucosa was evident. The surface epithelium had both ciliated and nonciliated cells and, particularly at the uterine body, often presented intra-epithelial macro...
Coyne CP, Fenwick BW, Iandola J, Williams D, Griffith G.Objectives of this investigation were to extract and isolate protein fractions inhibitory to the cytotoxic properties of tumor necrosis factor-alpha (TNF-alpha). In this context, mixed populations of WBC were harvested from equine blood and were stimulated with a combination of a synthetic chemotactic peptide and a calcium ionophore. Several methods were subsequently applied for the initial preparation of cell-free crude protein extracts, including fractional precipitation with gradient concentrations of ammonium sulfate and preparative-scale isoelectric focusing. In addition, protein fraction...
Jacobs PH, Elsinghorst TA.Endometrial cups in horses are outgrowths appearing in the uterine wall of the pregnant horn between approximately 38 days and 150 of gestation. The cups are structures which vary in shape from oval to irregular and have distinct raised edges, showing an ulcer-like form. The maximum measurements are approximately 5 X 2.5 X 2.5 cm. Microscopic examination shows that they consist of large epithelioid decidual-like cells having large nucleoli. Pregnant Mare Endometrium Gonadotrophin (PMEG) is produced in the endometrial cups. PMEG may be regarded as a precursor of Pregnant Mare Serum Gonadotrophi...
Larsdotter S, Holm L, Dahlborn K, Jansson A, Josefsson M, Ridderstråle Y.Sweat gland morphology and carbonic anhydrase (CA) distribution was studied after exercise in trained and untrained horses using a histochemical technique and light microscopic image analysis. Three trained and 3 untrained Standardbred trotters performed an exercise test (20 min trot at 6 m/s with 5 min walk at 1.8 m/s in the beginning and end) on a high-speed treadmill at 35 degrees C. Skin biopsies were taken before exercise and after trot. The fluid loss after exercise was 10, 12 and 12 g/kg bwt in the untrained horses and 4, 6 and 11 g/kg in the trained. Trained horses had a larger cell ar...
Lee OJ, Koch TG.Inflammation-associated disorders are significant causes of morbidity in horses. Equine single-donor mesenchymal stromal cells (sdMSCs) hold promise as cell-therapy candidates due to their secretory nonprogenitor functions. This has been demonstrated by mononuclear cell suppression assays (MSAs) showing that sdMSCs are blood mononuclear cell (BMC) suppressive in vitro. sdMSCs derived from umbilical cord blood are of clinical interest due to their ease of procurement, multipotency, and immunomodulatory ability. Due to the inherent donor-to-donor heterogeneity of MSCs, the development of robust ...
Thway TM, Wolfe MW.Primates and equids are the only species known to express the placental glycoprotein hormone, chorionic gonadotropin (CG), a heterodimeric glycoprotein composed of an alpha subunit linked to a hormone-specific beta subunit. The regulatory mechanisms involved in the induction of equine glycoprotein alpha subunit gene expression have not been identified. Epidermal growth factor (EGF) receptor is known to transduce signals that alter a number of different cellular functions (cell proliferation, differentiation, hormone secretion, and gene regulation). In the present study, we investigated the reg...
Vogelsang MM, Kraemer DC, Potter GD, Stott GG.Oocytes recovered by follicular aspiration were evaluated by light and transmission electron microscopy. Of the 22 oocytes, 4 exhibited characteristics of degeneration, and the remaining 18 were in various stages of meiotic development. Of the non-degenerate oocytes, 14 were in the germinal vesicle stage, 2 had undergone nuclear membrane disintegration, 1 displayed chromosomes in late metaphase I-early anaphase I, and 1 oocyte was in the process of extrusion of the first polar body. Although some oocytes retained complete cumulus cell investments, oocytes were predominantly enclosed only by th...
López ML, Fuentes P, Retamal C, De Souza W.The occurrence, localization and ultrastructural characteristics of a blood-tissue barrier throughout the stallion proximal seminal excurrent duct system were studied by the exclusion of electron-dense tracers and freeze-fracture techniques. Striking differences were observed in the distribution of lanthanum tracer and in the geometrical organization of the zonulae occludentes along the ductus efferentes, epididymides and vas deferens. The zonulae occludentes domain, the principal structural component of the blood-epididymis barrier, differed in permeability, width and strand numbers along the...
Alves BG, Alves KA, Hyde KA, Aguiar FLN, Souza SS, Brandão FAS, Garcia EC, Pinto Y, Gastal MO, Figueiredo JR, Teixeira DIA, Gastal EL.Ovarian tissue transplantation (OTT) is a technique well established and successfully applied in humans using mainly orthotopic or heterotopic transplantation sites. In livestock, OTT is still in its infancy and, therefore, different aspects of the technique, including the efficiency of different heterotopic OTT sites as well as the potential effect of age (i.e., young vs. old mares) in the ovarian graft quality, need to be investigated. The present study investigated the efficacy of the intramuscular (IM) or the novel subvulvar mucosa (SV) heterotopic autotransplantation sites to maintain the...
Manglai D, Wada R, Kurohmaru M, Yoshihara T, Kuwano A, Oikawa M, Hayashi Y.The present study attempted to clarify the characteristics of the guttural pouch mucosa in equines and to evaluate its foreign substance clearance ability. The specimens were collected from nine regions (eight in the guttural pouch mucosa, and one in the nasopharynx mucosa). We first examined the pouch mucosa by light and electron microscopy. We then measured the frequency of goblet cells per 200 epithelial cells, the length of the cilia, the thickness of the epithelial cell layer and lamina propria and statistically analyzed the data. The guttural pouch mucosa consisted of stratified columnar...
Salloum RM, Duckworth D, Madison JB, Souba WW.The sodium-dependent transporter system responsible for L-glutamine uptake by brush border membrane vesicles prepared from equine jejunum was characterized. Vesicle purity was ascertained by a 14- to 17-fold increase in activity of the brush border enzyme markers. Glutamine uptake was found to occur into an osmotically active space with negligible membrane binding. The sodium-dependent velocity represented approximately 80% of total uptake and demonstrated overshoots. Kinetic studies of sodium-dependent glutamine transport at concentrations between 5 microM and 5 mM revealed a single saturable...
Turek JJ, Lamar CH, Fessler JF, Bottoms GD.An in vitro system of cultured equine endothelial cells was evaluated as a model for endotoxin (ET) exposure in the horse. Primary cell lines from pulmonary vessels and aortas were cultured from tissues of 6 horses. Effects of ET alone with and without serum and in combination with the cyclo-oxygenase inhibitor flunixin meglumine and isolated equine neutrophils were evaluated by transmission electron microscopy. Cells plus serum were incubated with 10, 25, 50, or 100 micrograms of ET/ml of incubation medium for 1, 3, 8, or 24 hours. Cells without serum were cultured for 1 and 3 hours. Flunixin...
Whyte A, Allen WR.Pre- and post-implantation endometrial tissue was removed from equids at known stages of pregnancy. Thin sections of this material were reacted with fluorescein conjugates of several lectins. Two lectins in particular, with specificities for L-fucose and N-acetylglucosamine, reacted strongly with the endometrial epithelium. The reaction for N-acetylglucosamine occurred in small patches on the endometrial epithelium and extended to cover the entire epithelial surface and endometrial glands after implantation. L-Fucose was observed in larger surface deposits particularly at the openings of endom...
Weston MC, Collins ME, Cunningham FM.Inappropriately activated eosinophils can contribute to disease pathogenesis and intracellular signalling pathways that regulate functional responses may represent a therapeutic target. Little is known about intracellular signalling in equine eosinophils and this study examined the role of phospholipase C (PLC) and a range of protein kinases on responses to histamine and CCL11. Histamine (10(-4) M) or CCL11 (5.6 x 10(-9) M)-induced actin polymerization, migration and superoxide production by eosinophils from healthy horses were compared in the presence and absence of selective kinase inhibitor...
Oikawa M, Ohishi H, Katayama Y, Kushiro A, Yoshikawa H, Yoshikawa T.A mass developed in the mandibular gingiva of a thoroughbred racehorse. When the horse could no longer eat unassisted, it was killed and immediately autopsied. Macroscopically, the mandible exhibited extensive osteolysis, with only a small amount of bone remaining around the tooth roots. The cut surface of the mass around the mandible consisted of neoplastic medullary tissue, in which osteogenesis was observed. The medullary tissue was composed of pleomorphic medium-sized to large cells, interlaced by collagen bundles. These cells had large, pale, round or ovoid, sometimes cleaved nuclei, with...
Minelli A, Moroni M, Trinari D, Mezzasoma I.Ectoenzymic activities capable of hydrolyzing ATP sequentially to adenosine are present on equine epidydimal spermatozoa membranes. Kinetic parameters for ATPase, ADPase and 5'-nucleotidase were obtained by analysis of progress reactions curve when ATP, ADP and AMP were supplied as initial substrates. These values are not different from those found when the substrates were supplied from the preceding reactions. Feed-forward inhibition on 5'-nucleotidase by ATP/ADP was taken into account to fit simulated data to the experimental results. None of the substrates supplied by the preceding reaction...
Altunay H.The fine structure of the retinal pigment epithelium (RPE), Bruch's membrane and choriocapillaris was investigated by light and transmission electron microscopy in both the tapetal and non-tapetal fundus of the horse eye. In all locations, the RPE consisted of a single layer of low cuboidal cells. The epithelial cells were joined laterally by apically located tight junctions. These cells displayed numerous basal infoldings and abundant thin apical processes which enclosed the rod outer segments. The epithelial cell nuclei were large and located basally. Within the epithelial cells, smooth endo...
May SA, Hooke RE, Lees P.The presence, in equine synovial fluid, of inhibitors of interleukin-1 (IL-1) activity has been investigated by means of an assay involving IL-1-mediated production of PGE2 by synovial cells. Inhibitors of IL-1 alpha and IL-1 beta were identified in normal synovial fluid and synovial fluid from two horses with early joint disease. Inhibitors of IL-1 alpha were also present in synovial fluid from two horses with long-standing joint disease. However, IL-1 beta inhibitory activity was not present in fluid from the horses with more chronic joint disease. The effect appeared to be specific for IL-1...
Rapisarda G, Marino F, Ferrara G, Gioffrè F, Galofaro V.Here we present a case of preputial benign fibrous histiocytoma in a 7-year-old mule. This case was treated surgically. Pathologic analysis and diagnosis of these lesions were based on a combination of light microscopy and immunohistochemistry. Histologically, the tumour was composed primarily of a storiform pattern of fibroblastic and poligonal cells. In immunohistochemistry, except for consistent immunoreactivity for vimentin, nearly all tumour cells were positive for CD68, S-100 protein, pan-cytokeratin, alpha-smooth muscle actin, and desmin. Benign fibrous histiocytoma of the prepuce in mu...
