Histological and Histochemical Features of the Adrenal Gland, Kidney and Liver of the Many Laboratory Animals, Comparative Study

Objective: The aims of study to demonstrate and comparison the histological structures, histochemical and biochemical characteristics of adrenal glands, kidneys, and liver between the many laboratory animals and rodents (rabbit, cape hare, hamster, mice and guinea pig) directly involves living environment, metabolic and nutritional needs. Materials and methods: Seven animals from each species. Results: Histological results showed that the adrenal glands were encircled by capsule, three zones of cortex; glomerulosa, fasciculate, and reticularis, the medulla was made up of epinephrine and nor-epinephrine secreting cells. The kidney has been covered by a tiny amount of collagen and reticular fibers in all study animals, except in cape hare; the capsule was formed up of thick connective tissues. Renal corpuscles can be classified into; cortical, midcortical, and juxtamedullary. Proximal convoluted tubules were the longest, lined by cuboidal epithelial tissue had brush border. Henle loop comprises of a thin and thick limbs, were longer in mice and guinea pig compared to in other animals, and distal convoluted tubules were short and not brush border. Collecting tubules continues from the terminal part of distal tubule. All the corpuscle and nephron's lumen had a bigger diameter in cape hare compared with other animals. Bowman's capsules contained a more collagen fibers, as well as a thin space around the glomeruli in cape hare, but other animals' have large renal gaps and capsules contained fewer collagen fibers. The liver was enveloped by a thin capsule containing simple squamous epithelium with fibroconnective tissues, the parenchyma consisted of hepatocytes, as well as the central vein around these cells, divided by hepatic sinusoids and Kupffer cells protruded alongside the endothelial cells that lined the sinusoids. Histochemical results; brush border in kidneys and liver cells were take positive reaction to PAS. Biochemical tests appeared level of each the enzymes, and uric acid were significant differences between the animals. Because the kidney has little ability to filter out urea, an increase in urine volume is necessary as the urea load grows. The metabolic rate differs greatly amongst species. Conclusion: The findings demonstrated the hare's ability to adapt to its terrestrial habitat, as these qualities reduce the quantity of glomerular filtration, and differ in rate of metabolism caused by environmental factors or the animal's nutrition.