“The putative 5-hydroxytryptamine (5-HT) antagonists 2-bromo-LSD, cinanserin, cyproheptadine , pizotifen, methysergide, metitepine, mianserin and metergoline were found to reduce the frequency of the head-twitch response induced by intraperitoneal injections of 320 mg/kg of 5-hydroxytryptophan (5-HTP) in the rat.”