Topic:Cells
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.
Collection and cultivation in vitro of equine mammary macrophages. Equine macrophages were obtained from female Shetland ponies by injection of Escherichia coli lipopolysaccharide through the lactiferous ducts of the mammary gland. After 6 to 11 days, balanced salt solution was injected into the mammary gland to wash out accumulated cells. Harvested cells contained a mixture of macrophages, lymphocytes, and neutrophils, with the majority of the cells of mononuclear type. In culture, cells adherent after 24 hours were characterized as macrophages by morphologic features, nonspecific esterase staining, and by the presence of complement and immunoglobulin recept...
Ultrastructural features of Allantosoma intestinalis, a Suctorian ciliate isolated from the large intestine of the horse. Allantosoma intestinalis, a suctorian ciliate isolated from the intestine of the horse, was studied utilizing light and electron optical methods. These small sausage-shaped organisms have a varying number of tentacles (between one and 14) located at each extremity of the body. The microtubular axoneme of each tentacle in cross-section consists of two files of microtubules arranged in a daisy-like configuration. Haptocysts occur in the tentacle shaft, abutted to the plasma membrane of the knob of the tentacle, and in the cell body. The haptocysts are bottle-shaped, with prominent annular striat...
Antigenic and structural conservation of herpesvirus DNA-binding proteins. Previously, we have shown a common antigen of several herpesviruses (pseudorabies virus, equine abortion virus and bovine mammillitis virus) to be antigenically related to the major DNA-binding proteins of herpes simplex virus types 1 and 2. In this study we have purified the cross-reacting polypeptide from cells infected with pseudorabies virus, equine abortion virus and bovine mammillitis virus and shown the cross-reacting protein to be a major DNA-binding protein for each virus. Tryptic peptide analysis of the cross-reacting DNA-binding proteins of all five viruses has shown structural simi...
Equine immunology: an introductory review. This article attempts to relate some of the more recently accepted concepts of immunology to an understanding of the mechanisms of immunity in the horse. The cellular mechanisms involved in the immune response are outlined, with an indication of their likely role in humoral and cell-mediated immunity. In describing the humoral immune response, the structure and function of the different equine immunoglobulins are reviewed. The significance of humoral and cell-mediated immune responses are considered in relation to actively and passively acquired immunity.
Mobilization of iron from ferritin by isolated mitochondria. Effects of species compatibility between ferritin and mitochondria and iron content of ferritin. Mitochondria mobilize iron from ferritin by a mechanism that depends on external FMN. With rat liver mitochondria, the rate of mobilization of iron is higher from rat liver ferritin than from horse spleen ferritin. With horse liver mitochondria, the rate of iron mobilization is higher from horse spleen ferritin than from rat liver ferritin. The results are explained by a higher affinity between mitochondria and ferritins of the same species. The mobilization of iron increases with the iron content of the ferritin and then levels off. A maximum is reached with ferritins containing about 1 200 i...
The interaction of equine platelet tropomyosin with skeletal muscle actin. Whereas skeletal muscle tropomyosin binds strongly to muscle F-actin in a buffer containing 30 mM KCl and 1-2 mM free Mg2+, equine platelet tropomyosin only binds stoichiometrically (1 tropomyosin molecule per 6 actin monomers) at higher Mg2+ concentrations (7-8 mM free Mg2+). At low free Mg2+ concentrations (1.5 mM) the binding of the platelet protein is only marginally increased by raising the KCl concentration to an optimal value (0.10-0.20 M). This weaker binding can be attributed to the relatively poor head-to-tail polymerization of platelet tropomyosin and its fewer actin-binding sites. ...
Electron transfer between horse heart and Candida krusei cytochromes c in the free and bound states. Electron transfer between horse heart and Candida krusei cytochromes c in the free and phosvitin-bound states was examined by difference spectrum and stopped-flow methods. The difference spectra in the wavelength range of 540-560 nm demonstrated that electrons are exchangeable between the cytochromes c of the two species. The equilibrium constants of the electron transfer reaction for the free and phosvitin-bound forms, estimated from these difference spectra, were close to unity at 20 degrees C in 20 mM Tris-HCl buffer (pH 7.4). The electron transfer rate for free cytochrome c was (2-3).10(4)...
Nucleic acid-protein interactions. Degradation of double-stranded RNA by glycosylated ribonucleases. 1. Extensively glycosylated ribonucleases, like the enzymes from pig and horse pancreas, show a much higher activity on double-stranded RNAs than similarly charged, carbohydrate-free RNAases under stranded assay conditions (relatively high salt concentrations). Glycosylated pig and horse pancreas RNAases also show a larger destabilizing effect on double-stranded poly[d(A-T)] X poly[d(A-T)], than that displayed by bovine RNAase A under these conditions. Both activities show a similar dependence on the ionic strength of the medium. 2. A partial enzymic removal of the heterosaccharide side chains...
Separation and identification of equine leukocyte populations and subpopulations. Various methods of separation and identification of major equine leukocyte populations and subpopulations were used. The purity of T and B lymphocytes separated in Sephadex anti-equine F(ab')2 columns was 87% to 99% and 83% of 97%, respectively. The purity of T lymphocytes separated in nylon-wool columns was 89% to 98%. Preparations of B lymphocytes separated in glass-bead columns were 68% to 79% pure. The presence (or absence) of surface immunoglobulin by immunofluorescence was the most consistent and reliable method for the identification of B or T lymphocytes, respectively. However, the ery...
[Investigations on the individual-region distribution of adipocyte diameters by means of advanced statistical methods]. The dimensional distributions of the adipocytes in Equus caballus in many subjects and in many regions have been studied: such distributions turn out to be in good approximation galtonian ones. Furthermore, all the logarithm populations of the cell diameters have significantly the same variance. The used statistical methods (ANOVA two way with replications, and TUKEY -test) indicate an extremely significant different among the various regions (the smallest cells are in the supra-orbital fossa, the greatest ones are in the abdominal subserous floor).
Isolation of cellulolytic phycomycete fungi from the caecum of the horse. Microscopic examination of horse caecum contents revealed vegetative growth of phycomycete fungi on particles of digesta, and uniflagellated cells similar to fungal zoospores in the liquid phase. Three morphologically distinct isolates of strictly anaerobic phycomycete fungi were obtained from the caecum contents and cultured in vitro. Two of the isolates were able to utilize a wide range of plant carbohydrates for growth, including alpha-cellulose, xylan and particulate starch, and extensively digested water-insoluble plant tissues.
Procedure for granulokinetic studies in the horse with chromium-51. A procedure with chromium-51 (51Cr) as the cell label that maintains high-cell viability for studying granulocyte kinetics in horses is described. The procedure combines and modifies several methods for isolating leukocytes and granulocytes for use in the horse when a large volume of labeled cells is required. Also described is an improved technique for measuring granulocyte specific activity in large serial blood samples, using a Ficoll-sedimentation method. The procedure should be useful for determining granulocyte kinetics in the horse, the only major domestic species for which such data ar...
Intravascular neutrophilic granulocyte kinetics in horses. Intravascular granulocyte kinetics in 4 healthy horses were determined with chromium-51 as the cell label. The disappearance rate of labeled granulocytes was an exponential function. Mean total blood granulocyte pool (+/- 1 SD) was 5.65 +/- 1.514 X 10(8) granulocytes/kg of body weight, of which 2.71 +/- 0.715 X 10(8) granulocytes/kg were circulating and 2.94 +/- 0.876 X 10(8) granulocytes/kg were marginated along blood vessel walls. The mean disappearance half-life (T1/2) was 10.5 +/- 1.33 hours and the mean granulocyte turnover rate was 8.84 +/- 1.495 X 10(8) granulocytes/kg/day. A granulokin...
Congealed amniotic fluid in the alveoli of lungs of aborted foals. The alveoli of the lungs of 2 aborted foals contained elongated, dense bodies when examined histologically and by transmission and scanning electron microscopy. By light microscopy, the bodies (10 to 40 micrometers in size) stained intensely with the Gram stain, and up to 10 were present within an alveolus. Electron microscopy determined that such bodies were not cellular in origin but appeared to be a congealed fluid product composed of layers of fibrillar-like material. From the human literature, it was concluded that these intraalveolar bodies were probably congealed amniotic fluid.
Activation of pigeon erythrocyte adenylate cyclase by cholera toxin. Partial purification of an essential macromolecular factor from horse erythrocyte cytosol. A cytosolic, macromolecular factor required for the cholera toxin-dependent activation of pigeon erythrocyte adenylate cyclase and cholera toxin-dependent ADP-ribosylation of a membrane-bound 43,000 dalton polypeptide has been purified 1100-fold from horse erythrocyte cytosol using organic solvent precipitation and heat treatment. This factor, 13,000 daltons, does not absorb to anionic or cationic exchange resins, is sensitive to trypsin or 10% trichloroacetic acid and is not extractable by diethyl ether. Activation of adenylate cyclase by cholera toxin requires the simultaneous presence of AT...
Development of the adrenal cortex in the fetal foal: an ultrastructural study. The adrenal cortex from twelve fetal foals (gestational ages from 61 to 300 days) was examined by light and electron microscopy. Adrenal glands from three newborn foals were also examined by light microscopy. Between 61 and 100 days of gestation the adrenal cortex became organised into two distinct regions, the zona glomerulosa and zona fasciculata, which grew steadily in thickness until the 300th day. Between 300 days and birth there was a dramatic increase in the width of the zona fasciculata. From 200 days a narrow band of compact cells marked the cortico-medullary border. Though these cell...
Culture of horse oocytes in vitro. Oocytes were removed from follicles 5-30 mm in diameter. The germinal vesicle was present in 69.6% (23/33) of the oocytes at the start of culture, but after 20-24 and 40 h 70.5% (12/17) and 68.2% (43/63) of the oocytes were in metaphase I and metaphase II with first polar body extruded, respectively.
[Localization of beta-n-acetylhexosaminidase in stallion epididymis (author’s transl)]. The localization of beta-N-acetylhexosaminidase activity in 6 different segments of the epididymis was investigated in 8 stallions using biochemical and histochemical methods. The highest enzyme activity was found in segment D while the other segments displayed a much weaker reaction There was no or only low enzyme activity present in the epididymal fluid of the proximal 3 segments, whereas it was high in the distal 3 segments. The biological function of beta-N-acetylhexosaminidase in the epididymis is discussed briefly.