Question

name two substances that will only be found in efferent arteriole and afferent arteriole not in proximal tubule​

Answer 1

Explanation:

Efferent arterioles supply the blood for the extensive network of capillaries that surround the cortical and medullary tubular system of the kidneys, known as the peritubular capillary network.

Sympathetic Nerves

The afferent and efferent arterioles are innervated by sympathetic neurons; however, sympathetic tone is minimal when the volume of extracellular fluid is normal (see Chapter 6). Sympathetic nerves release norepinephrine and dopamine, and circulating epinephrine (which is a catecholamine like norepinephrine and dopamine) is secreted by the adrenal medulla. Norepinephrine and epinephrine cause vasoconstriction by binding to α1-adrenoceptors, which are located mainly on the afferent arterioles. Activation of α1-adrenoceptors decreases GFR and RBF. Dehydration or strong emotional stimuli, such as fear and pain, activate sympathetic nerves and reduce GFR and RBF.

Renalase, a catecholamine-metabolizing hormone produced by kidneys