Cytology and seasonal changes of the pituitary of the emballonurid bat,Taphozous melanopogon (Temminck)
The pituitary glands ofTaphozous melanopogon were examined histologically and cytochemically by employing several cytochemical staining techniques. The neural lobe is composed mostly of nerve fibres amidst which occur numerous small glial cells and a few Herring’s bodies. Two cell types have been identified in the pars intermedia. In addition to chromophobes, 5 different cell types, namely, 3 types of basophils (thyroid stimulating hormone, follicle stimulating hormone and luteinising hormone producing cells) and two types of acidophils (lactotrophic hormone and somatotrophic hormone producing cells), were identified in the pars distalis. The gonadotrophs and the lactotrophs aggregate in patches in certain regions of the pars distalis and exhibit cyclical changes in structure and number. The physiological significance of the cyclical changes of these cells is discussed in relation to the reproductive cycle of the animal.