title: Piracetam modifies morphine and related drug-induced elevation of serum corticosterone concentration in rats.
abstract: Piracetam (2-oxo-l-pyrrolidine acetamide, UCB 6215) or physiological saline solution was injected intravenously to female rats; after 60 min the animals were decapitated and blood was collected. Piracetam in doses of 100, 300 and 600 mg/kg resulted in a progressive suppression of serum corticosterone concentration (Cpd B) as compared to the controls. Morphine (5 and 10 mg/kg), nalorphine (5 and 10 mg/kg) and naloxone (0.5 mg/kg) induced a significant rise of Cpd B 30 min after subcutaneous injection, however, this could be prevented by 300 mg/kg piracetam given intraperitoneally 60 min prior to decapitation. Piracetam was ineffective in reducing the effects of high doses of morphine (20 mg/kg) and nalorphine (20 mg/kg). The drug had no effect on either ether stress or electric footshocks induced activation of the pituitary-adrenocortical system. In vitro the drug had no effect on pituitary ACTH release following exposure to crude hypothalamic extract. It is concluded that the effect of piracetam on the pituitary-adrenocortical axis is mediated through hypothalamic or extrahypothalamic brain structures and influences one of the effects of morphine and related drugs.
mesh_terms: D000818:Animals; D003345:Corticosterone / Q000097:blood*; D005260:Female; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects; D009020:Morphine / Q000494:pharmacology*; D009269:Nalorphine / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology; D010889:Piracetam / Q000494:pharmacology*; D010913:Pituitary-Adrenal System / Q000187:drug effects*; D011760:Pyrrolidinones / Q000494:pharmacology*; D051381:Rats; D013268:Stimulation, Chemical
chemical_list: D011760:Pyrrolidinones; D009270:Naloxone; D009020:Morphine; D009269:Nalorphine; D003345:Corticosterone; D010889:Piracetam