Rh. Rao, FASTING GLUCOSE-HOMEOSTASIS IN THE ADAPTATION TO CHRONIC NUTRITIONAL DEPRIVATION IN RATS, American journal of physiology: endocrinology and metabolism, 31(5), 1995, pp. 873-879
The hormonal basis for the metabolic paradox of relative hypoglycemia
despite insulinopenia and insulin resistance in chronic nutritional de
privation was studied in weanling rats restricted to 60% of ad libitum
intake over 8 wk (n = 12 each). Lower insulin and glucagon levels wer
e observed in both peripheral and portal blood (P = 0.0016) in the mal
nourished rats on multivariate analysis of variance, indicating decrea
sed islet secretion. Peripheral and portal hormone levels were proport
ionately similar, indicating that hepatic extraction was not altered.
Despite relative hypoglycemia, glucose turnover rate, total glucose ma
ss, and volume of distribution of glucose were not altered. This indic
ates that the sum total of the effects of malnutrition on the various
hormonal influences controlling glucose turnover had resulted in the e
stablishment of a new dynamic equilibrium associated with lower plasma
glucose levels. It is concluded that fasting glucose levels are susta
ined at a lower level in chronic malnutrition by an adaptive process t
hat includes insulin resistance and insulinopenia, counterbalanced not
only by glucagon resistance, as shown earlier, but also by decreased
glucagon secretion.