Kidney Hormones

Question 1

Renin

Answer 1

Secreted by JG cells in response to dEC renal arterial pressure and INC renal sympathetic discharge (β1
effect

converts angiotensinogen to angiotensin I

Question 2

AT II

Answer 2

Helps maintain blood volume and blood pressure

Affects baroreceptor function

limits reflex bradycardia, which would normally accompany its pressor
effects.

Question 3

ANP, BNP

Answer 3

Released from atria (ANP) and ventricles (BNP) in response to INC volume

act as a “check” on renin-angiotensin-aldosterone system

Dilates afferent arteriole, constricts efferent arteriole, promotes natriuresis

Question 4

ADH

Answer 4

INC aquaporin insertion in
principal cells

Primarily regulates osmolarity

also responds to low blood volume states

Question 5

Aldosterone

Answer 5

INC Na+ channel and Na+/K+ pump insertion in principal cells

enhances K+ and H+
excretion

Primarily regulates ECF volume and Na+ content

responds to low blood volume states

Question 6

Erythropoietin

Answer 6

Released by interstitial cells in peritubular capillary bed in response to hypoxia

Stimulates RBC proliferation in bone marrow.

Question 7

Caciferol

Answer 7

PCT cells convert 25-OH vitamin D3 to 1,25-

OH)2 vitamin D3 (calcitriol, active form

Question 8

Prostaglandins

Answer 8

Paracrine secretion vasodilates the afferent

arterioles to INC RBF.

Question 9

Dopamine

Answer 9

Secreted by PCT cells, promotes natriuresis

At low doses, dilates interlobular arteries, afferent
arterioles, efferent arterioles–>INC RBF, little or no change in GFR

At higher doses, acts as
vasoconstrictor.