Which two hormones are primarily responsible for regulating blood pressure?

The two hormones primarily responsible for regulating blood pressure are renin and angiotensin II. Renin is an enzyme secreted by the kidneys in response to low blood pressure, low sodium levels, or sympathetic nervous system stimulation. It catalyzes the conversion of angiotensinogen, a protein produced by the liver, into angiotensin I.

Angiotensin I is then converted into angiotensin II by angiotensin-converting enzyme (ACE), predominantly in the lungs. Angiotensin II is a potent vasoconstrictor, which means it narrows blood vessels, thereby increasing blood pressure. Additionally, angiotensin II stimulates the secretion of aldosterone from the adrenal glands, which in turn promotes sodium and water retention, contributing further to blood volume and pressure.

This interplay between renin and angiotensin II is crucial in the body's ability to maintain blood pressure homeostasis, especially during conditions of stress or hypovolemia. Other options listed do not play the same central role in the dynamic regulation of blood pressure through these mechanisms.