Prolactin responses to neuroleptics in normal and schizophrenic subjects.
The prolactin response to neuroleptics can serve as an index of dopamine blockade in humans. Plasma prolactin increments to single doses of chlorpromazine, and prolactin decrements to single doses of levodopa, were similar in normal and schizophrenic subjects. Antischizophrenic drugs of all chemical classes stimulated prolactin release,while chemically related drugs and other psychotropic agents ineffective in schizophrenia did not. The prolactin response to neuroleptic therapy occurred in all patients, and tolerance did not develop. Within subjects, prolactin responses were graded according to neuroleptic dose, but the upper limit of sensitivity of the response curve was achieved at doses below the therapeutic range. Relative prolactin-stimulating potency in humans of chlorpromazine, thioridazine, trifluoperazine, butaperazine, and haloperidol correlated well with their relative clinical potencies.
D002746:Chlorpromazine / Q000627:therapeutic use; D018492:Dopamine Antagonists; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D006220:Haloperidol / Q000627:therapeutic use; D006801:Humans; D010640:Phenothiazines / Q000627:therapeutic use; D011388:Prolactin / Q000097:blood*; D011954:Receptors, Dopamine / Q000187:drug effects; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy; D013881:Thioridazine / Q000627:therapeutic use; D014149:Tranquilizing Agents / Q000494:pharmacology* / Q000627:therapeutic use; D014268:Trifluoperazine / Q000627:therapeutic use
D018492:Dopamine Antagonists; D010640:Phenothiazines; D011954:Receptors, Dopamine; D014149:Tranquilizing Agents; D014268:Trifluoperazine; D011388:Prolactin; D006220:Haloperidol; D013881:Thioridazine; D002746:Chlorpromazine