Question

why would a high protein meal (high in arginine) increase GH and decrease SS but a prolong decrease in protein-caloric levels or fasting increase GH?

Answer 1

Increased protein diet or L-arginine increases the level of growth hormone by suppressing hypothalamic somatostatin which function to inhibit the pituitary gland's secretion of growth hormone. Apart from GH, L-Arg also stimulate insulin release from pancreatic β-cells. GH function to triggers protein anabolism which reflects by increasing amino acid uptake thereby increase protein synthesis and decreased oxidation of proteins. Studies reveal that L-arginie alone can elevate the GH by at least 100%.Fasting or prolong decrease in protein-caloric levels is found to increase GH level mediating via Insulin-like growth factor (IGF)-I that is a hormone produced primarily by the liver and regulated by growth hormone (GH) of the anterior pituitary gland.