A preliminary study of sex-related differences in prolactin responses to dopamine blockade and insulin hypoglycemia and in penfluridol plasma levels in schizophrenic patients.
Twelve healthy chronic schizophrenic patients were treated with the long-acting oral dopamine (DA) receptor blocker penfluridol (100 mg orally) for 6 weeks. Plasma prolactin (PRL) levels were measured during insulin-tolerance tests (ITT) performed at the end of the drug-free period (7-10 days) and during weeks 1 and 6 of penfluridol treatment. Simultaneous PRL and penfluridol plasma levels were determined just prior to, and at 8, 72 and 120 h after penfluridol administration during weeks 1, 5, and 6. During penfluridol treatment women (N = 4) had a greater increase in their maximal PRL increments after ITT as compared to the men (N = 8). Analyses of (peak) plasma penfluridol and PRL concentrations 8 h after penfluridol administration revealed a trend towards lower plasma penfluridol levels during weeks 5 and 6 and significantly higher PRL levels in women compared to men during weeks 1 (P less than 0.01), 5 (P less than 0.02), and 6 (P less than 0.02). The consistent sex-related differences in the PRL responses to DA blockade, and to insulin-induced hypoglycemia and in the penfluridol plasma levels in our study support the view that sex-related changes need to be considered not only in the hormonal responses to various pharmacological agents, but also in the assessment of the plasma levels of these drugs.
D000328:Adult; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000503:physiopathology; D007328:Insulin; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D010395:Penfluridol / Q000097:blood* / Q000627:therapeutic use; D010880:Piperidines / Q000097:blood*; D011388:Prolactin / Q000097:blood*; D011954:Receptors, Dopamine / Q000187:drug effects; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012737:Sex Factors
D007328:Insulin; D010880:Piperidines; D011954:Receptors, Dopamine; D010395:Penfluridol; D011388:Prolactin