What is the mechanism of action (MOA) of propofol?

Propofol is a widely used anesthetic agent known for its rapid onset and short duration of action. Its primary mechanism of action involves the enhancement of gamma-aminobutyric acid (GABA) receptor function in the central nervous system. Propofol achieves this by binding to a specific site on the GABA-A receptor, which increases the frequency of chloride ion channel opening when GABA binds to its site. This hyperpolarizes the neuronal membrane, making it less excitable and leading to sedation, anxiolysis, and amnesia.

This action is critical because it enhances the inhibitory tone in the brain, effectively contributing to the induction and maintenance of anesthesia. The ability of propofol to modulate GABA-A receptor activity is central to its utility in clinical settings, providing effective sedation with relatively few side effects compared to other anesthetics.

In the context of the other options provided, they do not accurately describe the pharmacological action of propofol. For instance, blocking NMDA receptors is more characteristic of drugs that have different anesthetic profiles, such as ketamine. Similarly, inhibiting GABA receptors would lead to excitatory effects, which is contrary to the purpose of an anesthetic. The activation of serotonin receptors does not