Abstract
Effect of β-endorphin and morphine injected intraventricularly on the release of immunoreactive Met-enkephalin, Leu-enkephalin and dynorphin 1–13 from the spinal cord was studied in anesthetized rats. Intraventricular β-endorphin, 16 μg, caused a marked spinal release of immunoreactive Met-enkephalin and to a much lesser extent, of immunoreactive Leu-enkephalin while intraventricular morphine, 40 μg, did not cause any significant release of immunoreactive enkephalins. The release of immunoreactive Met-enkephalin was not blocked by the pretreatment with 5 mg/kg naloxone, i.p. Immunoreactive dynorphin 1–13 was not released by either β-endorphin or morphine. High performance liquid chromatographic analysis indicated that immunoreactive Met-enkephalin released by β-endorphin had a retention time identical to [ 3H]Met-enkephalin. These findings in conjunction with previous pharmacological studies suggest different modes of pharmacological action for β-endorphin and morphine.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call