AJP - Endocrinology and Metabolism, Vol 241, Issue 2 146-E150, Copyright © 1981 by American Physiological Society
Somatostatin, insulin, and glucagon secretion from isolated perfused pancreas of obese rats
S. Seino, Y. Seino, J. Takemura, K. Tsuda, H. Kuzuya, K. Ishikawa, T. Shimazu and H. Imura
A comparison of the somatostatin with the insulin and glucagon secretions
in hypothalamic obesity and genetic obesity was made using the isolated
perfused pancreas of rats. In our perfusion experiment, the somatostatin
response to 19 mM arginine in the presence of 4.4 mM glucose was
significantly greater in both ventromedial hypothalamus (VMH)-lesioned and
Zucker fa/fa rats than in their controls, as was the perfusate insulin. The
perfusate arginine-stimulated glucagon secretion appeared no different in
obese and control rats. Because hyperinsulinemia in vivo and hyperresponses
to arginine of perfusate insulin and somatostatin were observed in both
VMH-lesioned and Zucker fa/fa rats, whereas the perfusate glucagon
secretion in the presence of 4.4 mM glucose was unchanged by obesity, the
secretory behavior of some pancreatic hormones seems similar in
VMH-lesioned and Zucker fa/fa rats in certain conditions. These results
suggest that some abnormalities of pancreatic hormone secretion may be
caused by a mechanism common to obesity, whether caused experimentally or
genetically.
