text: Only pMPPI [<< 4-iodo-N-[2-[4-(methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridynyl-benzamide hydrochloride >>], a selective [[ 5-HT(1A) ]] antagonist, was effective in inhibiting all 5-HT syndrome behaviors produced by lisuride, whereas pMPPI was without effect on any behavior induced by LSD.