Hypokinesia in mice and catalepsy in rats elicited by morphine associated with antidopaminergic agents, including atypical neuroleptics.
The interaction of morphine with agents displaying antidopaminergic properties (low dose of apomorphine, alpha-methyl-p-tyrosine, the "classical" neuroleptic haloperidol as well as the "atypical" neuroleptics sulpiride, thioridazine, clozapine and mezilamine) has been studied both on locomotor activity in mice and catalepsy in rats. At the tested doses most of the drugs induced neither catalepsy nor akinesia, but when they were associated with morphine these effects were plainly observed. It is suggested that a hyperactivity of dopaminergic systems mask the cataleptic effect of morphine.
D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D001058:Apomorphine / Q000494:pharmacology; D002375:Catalepsy / Q000139:chemically induced*; D003024:Clozapine / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D008297:Male; D008781:Methyltyrosines / Q000494:pharmacology; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects*; D010879:Piperazines / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013881:Thioridazine / Q000494:pharmacology; D019805:alpha-Methyltyrosine
D014150:Antipsychotic Agents; D008781:Methyltyrosines; D010879:Piperazines; D011743:Pyrimidines; D019805:alpha-Methyltyrosine; D009020:Morphine; D003024:Clozapine; D006220:Haloperidol; D001058:Apomorphine; D013881:Thioridazine; C014287:mezilamine