A counterregulatory hormone is a hormone that opposes the action of another.
Glucose CounterregulationEdit
The action of insulin is counterregulated by glucagon, epinephrine (adrenaline), norepinephrine (noradrenaline), cortisol, and growth hormone. These counterregulatory hormones—the term is usually used in the plural—raise the level of glucose in the blood by promoting glycogenolysis, gluconeogenesis, ketogenesis, and other catabolic processes.<ref>Template:Cite journal</ref> In healthy people, counterregulatory hormones constitute a principal defense against hypoglycemia, and levels are expected to rise as the glucose falls.
As an example, the exercise-induced reduction in blood glucose is counterregulated by increases in levels of epinephrine, norepinephrine, cortisol, and growth hormone. The 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.
Blood Pressure CounterregulationEdit
Similarly, the natriuretic peptides counterregulate against renin, angiotensin, and aldosterone which elevate blood pressure.<ref>Template:Cite journalTemplate:Verify source</ref>
Reproductive CounterregulationEdit
In the reproductive system, inhibins and follistatin counterregulate activins, to control follicle-stimulating hormone and so the release of gonads.<ref>Template:Cite journalTemplate:Verify source</ref> Inhibins and activins also regulate bone mass.<ref>Template:Cite journal</ref>