A student ask the pharmacology instructor to describe the function of cholinergic agonist. What would be the instructor's reply?

A) Decrease in heart rate and perfusion, and an increase in inflammatory response: These manifestations suggest parasympathetic nervous system activation, not the sympathetic response. The sympathetic system generally increases heart rate and perfusion to support "fight or flight" responses. Additionally, inflammatory responses are more immune-related and are not a direct effect of sympathetic activation.

B) Increase motility and secretion in the GI tract, constriction of bronchi and pupils: This is characteristic of parasympathetic nervous system activity. The parasympathetic system stimulates digestion (increased motility and secretion) and causes bronchoconstriction and pupil constriction (miosis). The sympathetic nervous system, in contrast, inhibits GI motility and causes bronchodilation and pupil dilation.

C) Increase in blood pressure, bronchodilation, and decrease bowel sounds: These are hallmark signs of sympathetic nervous system activation. When the sympathetic system is activated during stress or danger, it leads to vasoconstriction, which increases blood pressure. Bronchodilation occurs to allow more oxygen intake, and GI motility decreases (manifested as reduced bowel sounds) to redirect energy to more vital functions, like increased circulation to muscles.

D) Decrease in sweating, decrease in respiration, and pupil constriction: These signs suggest parasympathetic or a relaxed state. The sympathetic nervous system typically increases sweating, respiration, and causes pupil dilation to prepare the body for increased activity. Decreased sweating and respiration, along with pupil constriction, would not be consistent with the sympathetic response.

A) Sweating: Sweating is a function of the sympathetic nervous system, not the parasympathetic nervous system. The sympathetic nervous system is responsible for the "fight or flight" response, which includes activating sweat glands. The parasympathetic system, in contrast, is more involved in "rest and digest" functions.

B) Pupil dilation: Pupil dilation (mydriasis) is mediated by the sympathetic nervous system through the activation of alpha-1 adrenergic receptors. The parasympathetic system causes pupil constriction (miosis) by stimulating muscarinic receptors in the eye, which is the opposite of pupil dilation.

C) Vasoconstriction: Vasoconstriction (narrowing of blood vessels) is generally a
function of the sympathetic nervous system, which releases norepinephrine to constrict blood vessels and increase blood pressure. The parasympathetic system typically causes vasodilation (widening of blood vessels) to promote relaxation and decreased blood pressure.

D) Anabolism: Anabolism refers to the metabolic processes that build up molecules and store energy, such as protein synthesis, cell growth, and energy storage. This is primarily mediated by the parasympathetic nervous system, which is involved in "rest and digest" functions. The parasympathetic system promotes activities that support energy conservation, digestion, and tissue repair, all of which support anabolic processes.