Is there an undiscovered neurocircuit for regulating GH secretion? -Pitfalls of GHRP-2 and ITT as GH provocative tests-

The arginine and GHRP-2 tests as alternatives to the insulin tolerance test for the diagnosis of adult GH deficiency in Japanese patients: A comparison

“…Insulin-induced hypoglycemia and arginine stimulate GH secretion by suppressing endogenous somatostatin secretion in the hypothalamus [14,15]. GHRP-2 is a potent synthetic GH secretagogue, which acts on a specific receptor at the hypothalamic arcuate nucleus-median eminence to potentiate GH-releasing activity [16,17]. On the other hand, GHRH acts directly on the pituitary somatotroph to cause GH secretion.…”