Histamine release induced by dynorphin-(1-13) from rat mast cells

Abstract

Dynorphin is a potent opioid peptide. A synthetic dynorphin-(1-13) (Dyn) induced histamine release accompanied by degranulation from isolated rat mast cells in a dose-dependent manner over the concentration range 10(-7)-10(-5) M. Dynorphin-(1-13)-induced histamine release completed within 10 sec at 37 degrees C, and the release was not accompanied by the leakage of lactate dehydrogenase. Calcium (10(-5)-10(-3) M) enhanced the release, although higher concentration than 10(-3) M suppressed the release. The pH for the maximum release by Dyn was about 7.3. Disodium cromoglycate (5 X 10(-6)-10(-4) M) inhibited the histamine release by Dyn, but naloxone and leucine-enkephalin did not. These results indicate that Dyn-induced histamine release was not mediated by opioid receptors of the mast cells. Its mode of action appeared to that of anaphylactic histamine release.