In vivo incorporation of l-[ 3H]arginine into proteins of anterior pituitary gland and hypothalamus of infact and castrated rats

Abstract

The in vivo incorporation of [ 3 H]arginine into proteins of different regions of hypothalamus and anteriot pituitary gland (APG) of intact and castrated rats has been studied. Three and 6 weeks after castration of the concentration of protein and incorporation of arginine into proteins of APG, anterior and median hypothalamus increased significantly. The concentration of protein and incorporation of arginine by posterior hypothalamus and cerebral cortex were unaffected by castration. Autoradiographic localization also showed an intense labeling of the neurons in the suprachiasmatic and arcuate nuclei, suggesting that these neurons might be involved in the synthesis of FSH-LH releasing hormones(s). Short-term treatment with diethyl stilbestrol (DES) inhibited the castration-induced increase in concentration of protein as well as amino acid incorporation into proteins of both APG and anterior and median hypothalamus. DES did not cause any change in the protein synthetic activity of posterior hypothalamus and cerebral cortex.