Ghrelin Ghrelin Ghrelin (pronounced ), the "hunger hormone", also known as lenomorelin (INN), is a peptide hormone produced by ghrelinergic cells in the gastrointestinal tract that functions as a neuropeptide in the central nervous system. Besides regulating appetite, ghrelin also plays a significant role in regulating the distribution and rate of use of energy. When the stomach is empty, ghrelin is secreted. When the stomach is stretched, secretion stops. It acts on hypothalamic brain cells both to increase hunger, and to increase gastric acid secretion and gastrointestinal motility to prepare the body for food intake. The receptor for ghrelin, the ghrelin/growth
Counterregulatory hormone rise in blood concentrations of these counterregulatory hormones is dependent upon both exercise intensity and duration, and is proportional to the rate of glucose uptake by the contracting skeletal muscle. Similarly, the natriuretic peptides counterregulate against renin, angiotensin, and aldosterone which elevate blood pressure. In the reproductive system, inhibins and follistatin counterregulate activins, to control follicle-stimulating hormone and so the release of gonads. Inhibins and activins also regulate bone mass. Counterregulatory hormone A counterregulatory hormone is a hormone that opposes the action of another. The action of insulin is counterregulated by glucagon, epinephrine (adrenaline), norepinephrine (noradrenaline), cortisol, and growth hormone.