Comparative studies on histology, histochemistry and ultrastructure of the adrenal medulla of carnivore fennicus, vulpes zerda and herbivore rabbit, oryctolagus cuniculus

ABSTRACT

The present study of the adrenal medulla of two examined animals, carnivore Vulpes zerda and herbivore Oryctolagus cuniculus demonstrated that they have differences in the form of medulla. Both have two populations of medullary cells. Norepinephrine cells [NE] exhibited intense staining with hematoxylin or toluidine blue [basic dyes] and they have specific characteristic morphological features, arrangement and location. The other population, the epinephrine cells [E] that represent most of the medullary cells stained faintly and distributed homogenously through the medulla. The histochemical techniques illustrated the existance of acid mucopolysaccharides in the medullary cells in both types animals being more pronounced in carnivore than herbivore. The carbohydrates are present in a fair amount in Vulpes medullary cells although they are found in weak amounts in Oryctolagus. The total proteins are displayed in most of the medullary epinephrine cells in moderate amounts, and more in norepinephrine cells of both types of examined animals. TEM examination revealed many differences between the two types of studied animals. They are summarized as mitochondrial shape, nuclei of epinephrine and norepinephrine cells, and the distribution of vacuoles