The influence of acute hyperinsulinemia on the insulin-related material in brain, testis, liver, and kidney.
Insulin-related material was measured in acid ethanol extracts of brain, testis, liver, and kidney from adult rats acutely injected with insulin or saline. Insulin injection resulted in a twofold to threefold increase in plasma insulin during a two-hour period after injection. Plasma glucose was greatly depressed. Insulin injection had no effect on the insulin-related material in most areas of brain (cerebral cortex, olfactory bulbs, and medial hypothalamus) and the cerebrospinal fluid; lateral hypothalamus was an exception and paradoxically exhibited a decrease of this material. The testis insulin-related material was unaffected; purification of the testis extracts using the C18 Sep pak method revealed no further difference between the animals. In liver, the insulin-related material was not significantly different in the control and the insulin-injected group; however, we found a significant correlation between this material and plasma insulin within the insulin-injected group. In contrast, insulin injection resulted in an important increase in kidney insulin-related material that paralleled the change in plasma insulin. Thus, like chronic experiments, acute hyperinsulinemia revealed that the insulin-related material was largely independent from blood insulin in tissues that exhibit very different insulin uptake from the blood; kidney appeared to be an exception.
Manin
M
M
Laboratoire d'Etude du Métabolisme Azoté, INRA-Theix, Ceyrat, France.
Mizrahi
M
M
Vye
P
P
Balage
M
M
Grizard
J
J
D000818:Animals; D001921:Brain / Q000378:metabolism*; D006946:Hyperinsulinism / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008297:Male; D009928:Organ Specificity; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000378:metabolism*
D007328:Insulin