PSY396H1 Study Guide - Final Guide: Gaba Receptor Antagonist, Bulgarian State Railways, Gaba Receptor
Document Summary
Psy396 lecture 9 therapies, barbiturates, benzodiazepines, antidepressants & -adrenergic antagonists. Anxiolytics (1st and 2nd generation: work by enhancing gaba transmission to reduce excitability (increasing inhibition) Sleep aids and sedatives used early on, now use depressants to reduce neuron excitability. High doses of anxiolytics can lead to sedation sleep anesthesia coma death. Sedative-hypnotic drugs cns depressants to reduce neuron excitability: benzodiazepines, barbiturates, alcohol. Gabaa receptor a cl channel, hyperpolarizes neuron gaba binds and allows cl to flow in. Binds to gabaa receptor (at different site from benzodiazepines) Open cl channel without gaba (potentiate), stay open longer. Repeated use increases liver microsomal enzymes enhances drug metabolism lower blood levels of barbiturate. More barbiturate dose needed for same effect after repeated use because you increase breakdown by increasing liver enzymes. Increase effective dose means it comes closer to the lethal dose (low margin of safety = td50 ed50, low therapeutic index = td/ed)
