Buspirone HCl

Buspirone, a clinically effective non-benzodiazepine anxiolytic drug, causes inhibition of firing of these neurons when given by intravenous (ED50 = 0.011 mg/kg, i.v.), intraperitoneal (ED50 = 0.088 mg/kg, i.p.), and intragastric (effective dose = 1.0-20.0 mg/kg, i.g.) injection. Buspirone also inhibits these cells when it is administered to the outside of recorded neurons by microiontophoresis. ^[1] Buspirone is eliminated primarily by oxidative metabolism, which produces several hydroxylated metabolites, including 5-hydroxy-buspirone and 1-pyrimidinylpiperazine. ^[2]

Buspirone (3 mg/rat, i.p.) dose dependently and completely inhibits shock-induced ultrasonic vocalization after systemic injection and after microinjection into the dorsal raphe nucleus of rats, a brain region rich in somatodendritic 5-HT1A receptors. ^[3] Buspirone (20 mg/kg) decreases immobility in the rat forced swim test. ^[4] Buspirone is a serotonergic (5HT(1A) receptor agonist) anxiolytic drug with some D(2) dopaminergic effect in a zebrafish model of anxiety. ^[5] Buspirone dose-dependently reduces LID and improved l-DOPA-related motor performance due to action at the 5-HT(1A) receptor in l-DOPA-primed rats. Buspirone delayes LID development while improving l-DOPA's anti-parkinsonian efficacy indicating the potential long-term benefits of 5-HT(1A) agonists for reduction of l-DOPA-related side effects in l-DOPA-naive rats. ^[6]