<prompt> GH level increases duringREM sleepHypoglycaemiaIncreased cortisolHyperglycemia  <response>: B Hypoglycaemia Stimulators of Growth Hormone GH secretion include: Peptide hormones: GHRH somatocrinin through binding to the growth hormone-releasing hormone receptor GHRHR Ghrelin through binding to growth hormone secretagogue receptors GHSR Sex hormones: Increased androgen secretion during puberty in males from testis and in females from adrenal cortex Estrogen: Clonidine and L-DOPA by stimulating GHRH release a4b2 nicotinic agonists, including nicotine, which also act synergistically with clonidine. Hypoglycemia, arginine and propranolol by inhibiting somatostatin release Deep sleep Niacin as nicotinic acid Vitamin B3 Fasting Vigorous exercise Inhibitors of GH secretion include: GHIH somatostatin from the periventricular nucleus Circulating concentrations of GH and IGF-1 negative feedback on the pituitary and hypothalamus Hyperglycemia Glucocorticoids Dihydrotestosterone In addition to control by endogenous and stimulus processes, a number of foreign compounds xenobiotics such as drugs and endocrine disruptors are known to influence GH secretion and function. 