The Fine Structure of the Adrenal Gland of the Indian SheathTailed Bat, Taphozous longimanus (Hardwicke)

Abstract

The Indian sheath-tailed bat, Taphozous longimanus at Nagpur (Maharashtra State) shows continuous asynchronous breeding, exhibiting aseasonal polyoestry. The adrenal gland of Taphozous is made up of the steroidogenic and chromaffin cells. The ultrastructural features of the glomerulosa cells during estrus are inconspicuous Golgi complex mitochondria with vesicular cristae, a few lipid droplets and smooth endoplasmic reticulum with vesicular cisternae. Numerous mitochondria, smooth endoplasmic reticulum in the form of interconnected vesicles scattered throughout the cytoplasm and large numbers of lipid droplets are the characteristics of the cells of zona fasciculata. Adrenal gland of pregnant female shows striking differences in ultrastrctural features than those observed in the adrenal gland of non-pregnant female. During pregnancy, the cells of zona glomerulosa are hypertrophied and synthetically very active than that observed during estrus. The cells of zona fasciculata show mitochondria with tubular and lamellar cristae. There is an increase in GolgiSER area during pregnancy as compare to estrus. Lipid droplets are more than those observed in the cells of zona glomerulosa and zona fasciculata of estrus adrenal. The close association of lipid droplets with smooth endoplasmic reticulum and mitochondria suggests the active biosynthesis of steroid hormones. Adrenal medulla consists of two types of cells depending on the presence of secretory granules. Nor-epinephrine cells are predominant in the medulla of pregnant bat while epinephrine cells are predominant in the medulla of estrus bat. Keywordsbat, adrenal cortex, medulla, ultrastructure, reproductive cycle.