THE RELATIONSHIP OF THE ANTERIOR PITUITARY AND THE ADRENAL CORTEX IN THE METABOLISM OF CARBOHYDRATE

Abstract

Normal and adrenalectomized rats, with and without treatment with adrenal cortical extract (C.) or ant. pituitary extract (A.P.), were fasted and then fed known amts. of glucose; disposition of the absorbed glucose was indicated by detn. of the R.Q. and deposition of glycogen in liver and muscles. In normal rats, both A.P. and C. (when given in large amts.) depressed glucose oxidation and promoted glycogen deposition, the former in muscle only, the latter more markedly in the liver. In adrenalectomized rats, the A.P. failed to act; large amts. of C. increased the liver glycogen at the expense of oxidation, as in the normal, but had no effect on muscle glycogen. When A.P. and C. were given to adrenalectomized rats the usual action of A.P. was evident. Since this effect was observed when the dose of C. was too small to be effective by itself, A.P. and C. apparently have a synergistic as well as complementary action on the metabolism of glucose in rats. In fasted rats, A.P. maintained muscle glycogen levels in the absence of the adrenal cortex, without affecting the liver glycogen or blood sugar levels; this action is in contrast to that of C, which increases liver glycogen stores and blood sugar levels but does not affect muscle glycogen directly.