Direct-Werkende Cholinerge Agonisten: Chemie en Relatie Tussen Structuur en Activiteit

Cholinergic agonists mimic the actions of ACh, and such cholinomimetics are either direct- or indirect-acting agents.

Direct-acting agonists bind to and activate both muscarinic and nicotinic receptors and induce a response longer than ACh.

They are categorized as—choline esters and their synthetic derivatives and naturally occurring alkaloids.

ACh—the endogenous choline ester, features an ethylene bridge linking a charged quaternary ammonium to an ester group, facilitating ACh binding to the receptor.

The ester group is, however, susceptible to AChE enzyme, which hydrolyzes ACh and terminates its action.

Synthetic choline esters are derived from ACh. They have subtype selectivity and are resistant to enzymatic hydrolysis. Presence of an additional –CH₃ group in the linker imparts enhanced selectivity for muscarinic receptors.

Naturally occurring alkaloids include tertiary and quaternary amines, which exhibit receptor specificity and are unaffected by AChE enzyme.