Mescaline: excitatory effects on acoustic startle are blocked by serotonin2 antagonists
Psychopharmacology November 1, 1987 M. Davis 23 citations
Mescaline (20 mg/kg) consistently increases the amplitude of the acoustic startle reflex in rats. This excitatory effect is blocked in a dose-related manner by the serotonin2 (5-HT2) antagonist ritanserin (ED50 dose = 0.25 mg/kg IP), while even a high dose of ritanserin (2.0 mg/kg) does not block the excitatory effects of amphetamine on startle. Other 5-HT2 antagonists (ketanserin, cinanserin, LY 53857) also block mescaline's effect, but the 5-HT1 antagonist pindolol (5 mg/kg) does not. These findings support the hypothesis that hallucinogens' behavioral effects are mediated by agonist actions at 5-HT2 receptors.