The effect of histamine on the isolated rat common carotid, renal and cranial mesenteric arteries was examined. Histamine (10-8 - 10-4 m) caused concentration-dependent relaxations of the arteries during contractions induced with phenylephrine (10-8 - 10-7 m). Removal of the vascular endothelium inhibited the histamine-induced relaxations. Pyrilamine (6 × 10-6 m), but not metiamide (10-6 m), abolished the relaxant effect of histamine. Moreover, pyrilamine (6 × 10-6 m) did not affect endothelium-dependent relaxations of the arteries produced with acetylcholine. These results indicate that histamine causes endothelium-dependent relaxations of the rat peripheral large conduit arteries, which appeared to be mediated via H1-histaminergic receptors.
ASJC Scopus subject areas
- Physiology (medical)