Ghrelin capacity for food but also dramatically lowers ghrelin levels compared to both lean controls and those that lost weight through dieting alone. However, studies are conflicting as to whether or not ghrelin levels return to nearly normal with gastric bypass patients in the long term after weight loss has stabilized. Bariatric surgeries involving vertical-sleeve gastrectomy reduce plasma ghrelin levels by about 60% in the long term. Ghrelin plasma concentration increases with age and this may contribute to the tendency for weight gain as people age. Ghrelin Ghrelin (pronounced ), the "hunger hormone", also known as lenomorelin (INN), is a peptide
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.