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 s at 37.degree. C, and the release was not accompanied by the leakage of lactate dehydrogenase. Ca (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 .apprx. 7.3. Disodium cromoglycate (5 .times. 10-6 to 10-4 M) inhibited the histamine release by Dyn, but naloxone and leucine-enkephalin did not. Dyn-induced histamine release was apparently not mediated by opioid receptors of the mast cells. Its mode of action appeared to be that of anaphylactic histamine release.