β Endorphin, an opiate like peptide, has potent antinociceptive properties when it is administered directly into the brain and assayed in the tail flick, hot plate, and writhing tests in mice and in the wet shake test in rats. On a molar basis, β endorphin is 18 to 33 times more potent than morphine and its actions are blocked by the specific opiate antagonist, naloxone hydrochloride. The activity of β endorphin in vivo is also compared to other peptides that show opiate like activity in assays in vitro.
|Original language||English (US)|
|Number of pages||4|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - 1976|