Does neuroleptic blocking of dopamine receptors continue after chronic treatment?
Neuroleptic treatment of schizophrenia reduces CSF cyclic AMP in clinical responders after a mean of 8 weeks of treatment. This is consistent with continued effective dopamine receptor blockade by these drugs. Rat striatal 3H-spiroperidol binding sites increase more after 10 weeks of haloperidol therapy than after 3 weeks, suggesting that physiological equilibrium has not yet been reached by 3 weeks. The rat striatal receptor affinity for 3H-spiroperidol is decreased after 10 weeks but not after 3 weeks. The decreased affinity represents a new phenomenon that may be important in explaining long-term continuing neuroleptic effectiveness despite the increased receptor number. The decreased affinity of rat dopamine binding sites for 3H-spiroperidol after 10 weeks of neuroleptic treatment is consistent with the reduced human CSF cyclic AMP after a similar period of neuroleptic treatment.
D000293:Adolescent; D000328:Adult; D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D003342:Corpus Striatum / Q000378:metabolism; D000242:Cyclic AMP / Q000134:cerebrospinal fluid; D006152:Cyclic GMP / Q000134:cerebrospinal fluid; D005260:Female; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D051381:Rats; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D012559:Schizophrenia / Q000188:drug therapy* / Q000378:metabolism
D014150:Antipsychotic Agents; D011954:Receptors, Dopamine; D000242:Cyclic AMP; D006152:Cyclic GMP; D006220:Haloperidol