The sigma receptor ligand (+/-)-BMY 14802 prevents methamphetamine-induced dopaminergic neurotoxicity via interactions at dopamine receptors.

The possibility that compounds which interact with the putative sigma receptor might influence the dopaminergic neuropathology produced by the administration of methamphetamine (METH) to mice was investigated. (+/-)-BMY 14802 [alpha-(4-fluorophenyl)-4-(5-fluoro-2-pyrimidinyl)-1-piperazine-butanol hydrochloride] attenuated METH-induced dopaminergic neuropathology whereas several other sigma-acting compounds such as R-(+)-3-(3-hydroxyphenyl)-N-propylpiperidine hydrochloride, 1,3-di-o-tolyl-guanidine, rimcazole, clorgyline or (-)-butaclamol did not alter neurotoxicity produced by this central nervous system stimulant. (-)-BMY 14802, which has a lower affinity for the sigma site than (+)-BMY 14802, was more potent than (+)-BMY 14802 in antagonizing METH-induced neuropathology. In addition, the ketone metabolite (BMY 14786; alpha-(4-fluorophenyl)-4-(5-fluoro-2-pyrimidinyl)-1-piperazine-butanone hydrochloride), which is a major metabolite formed from (-)-BMY 14802, also attenuated the METH-induced effects. (+/-)-BMY 14802 pretreatment of mice prevented the reduction in D1 and D2 dopamine receptor number produced by the systemic administration of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline and demonstrates that (+/-)-BMY 14802 and/or its metabolites interact with the dopamine receptor subtypes. Taken together, these findings suggest that the protective effect of (+/-)-BMY 14802 against METH-induced neuropathology is mediated, at least in part, through dopamine receptor antagonism. Furthermore, the failure of other sigma-acting compounds to alter METH-induced neurotoxicity indicates that the putative sigma receptor is unlikely to be an important mediator in this type of neuropathology.

Butaclamol in the treatment of schizophrenia. A standard-controlled clinical trial.

A 16-week, standard-controlled, double-blind study was conducted to compare the efficacy of butaclamol with that of fluphenazine in the treatment of 24 newly admitted schizophrenic patients. Statistically significant improvement occurred in the entire population in the total scores of the BPRS and PAS; in the activation, anergia, thought disturbance and hostile/suspiciousness factor scores of the BPRS; and in the scores of 9 of the 12 factors of the PAS. There were no statistically significant differences between the scores of the two treatment groups on the total or factor scores of either scale during the course of the clinical trial. The most frequently occurring adverse effects in the butaclamol group were rigidity, akathisia and excitement/agitation. The most frequently occurring adverse effects in the fluphenazine group were insomnia, decreased motor activity and tremor. It is concluded that butaclamol exerts potent neuroleptic effects on schizophrenic patients.

Butaclamol in newly admitted chronic schizophrenic patients: a modified fixed-dose dose-range design.

In a double-blind placebo controlled study of newly admitted chronic schizophrenics, an attempt was made to further evaluate the safety, acceptability, and effectiveness of BT in doses of 10, 20, and 40 mg. Significant dose related responses occurred on several behavioral variables by the first week of treatment. Maximum clinical response appeared to be at the 20-40 mg. dose level. Extrapyramidal signs occurred at all doses, but with greater severity at higher doses. Excessive daytime drowsiness occurred in all groups but with longer duration and greater intensity in the 20 mg. group. Rebound insomnia occurred after the abrupt withdrawal of BT at all dose levels suggesting the desirability of further study of its hypnotic properties.