Diuresis and suppression of vasopressin by kappa opioids: comparison with mu and delta opioids and clonidine.

摘要: The effects of agonists at kappa, mu and delta opioid receptors were determined on vasopressin levels in water-deprived rats. Bremazocine U-50, 488 (kappa agonists) markedly suppressed levels, whereas morphine methadone (mu metkephamid (a mixed agonist) did not suppress levels. Likewise, clonidine, a potent diuretic normally hydrated rats, clearly Metkephamid was shown to have modest effect rats but bremazocine blocked completely by simultaneous treatment with desmopressin, synthetic vasopressin-like analog. Desmopressin also the waterload, only partially attenuated clonidine. These results support hypothesis that kappa produce suppressing plasma vasopressin, higher doses pattern urination similar animals lacking vasopressin. By comparison, little