Immunolocalization of glucagon and insulin cells in endocrine pancreas and cyclic disparity of plasma glucose in the lizard psammophilus dorsalis

Reptiles are an interesting group to study the physiology of reproduction. As information on mobilisation of glucose and associated endocrine alterations in the pancreas are not known, a study on the lizard Psammophilus dorsalis was undertaken using immunohistochemistry. Glucagon-immunoreactive (IR) and insulin-IR cells never formed islets instead spread throughout the pancreas in P. dorsalis. Glucagon-IR cells appeared to release the secretory granules from all over the surface, insulin-IR cells are unidirectional in their secretion. Both cell types often have no direct contact with capillaries. The morphometric analysis showed that the glucagon-IR cells were the most abundant amounting approximately 63 % as against insulin-IR cells, amounting approximately to 37 % of the endocrine pancreatic mass in the present study. On an average P. dorsalis exhibited 288.3 ± 25.28 mg% of plasma glucose, the abdominal fat underwent clearance as there was energy demand during reproductive and recrudescent periods. Glycogen granules were evident in liver and this was inversely related with plasma glucose