Glucagon levels in pancreatic extracts and plasma of the lizard (1).

Levels of glucagon in the splenic pancreas and in plasma of the lizard Anolis carolinensis were estimated by radioimmunoassay. The splenic pancreas of Anolis has a glucagon concentration nearly a 1000 times greater, on a weight basis, than that of the mammalian pancreas. Glucagon-like immunoreactivity (GLI) of anolian plasma varied over a wide range, but relative to mammals the GLI levels were inappropriately elevated for the concentration of plasma glucagon secretion, particularly as related to alpha cell function in the diabetic state.