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NE can stimulate its own release by agonizing:

a) Alpha-1 receptors
b) Beta-1 receptors
c) Alpha-2 receptors
d) Beta-2 receptors

User Bapho
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1 Answer

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Final answer:

Norepinephrine stimulates its own release by agonizing alpha-2 receptors (option c) , which are involved in a negative feedback mechanism that controls neurotransmitter release.

Step-by-step explanation:

The question pertains to the self-stimulation of norepinephrine (NE) release through adrenergic receptors. Norepinephrine can stimulate its own release by agonizing alpha-2 receptors. These receptors, when activated, can inhibit the further release of NE; however, in the context of the autoregulation of NE release, the alpha-2 receptor acts in a feedback mechanism to control the release of NE. This is in contrast to alpha-1, beta-1, and beta-2 receptors, which have different roles in the body's response to catecholamines.




The mechanism by which the alpha-2 receptor works involves coupling to Gi proteins, which results in a decrease of cAMP activity within the cell, ultimately leading to cellular effects such as smooth muscle contraction. The alpha-2 adrenergic receptor has three subtypes - α2A, α2B, and α2C - each with specific actions in different tissues, including the inhibition of insulin release in the pancreas.

User Curiouslychris
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