Abstract: AIM: To compare the effects of histamine and its antagonists on tension of isolated rabbit basilar and mesenteric artery in vitro, and to observe the role of Ca²⁺ in histamine-induced response. METHODS: The doseresponse curves induced by histamine were recorded on the isolated rabbit central and peripheral arteries in different doses of diphenhydramine, cimitidine, and nifidipine. RESULTS: Histamine could cause contraction of basilar and mesenteric isolated arteries. Diphenhydramine and nifidipine antagonized these effects, while cimitidine enhanced this effect. CONCLUSION: There may be different receptors densities in different rabbit arteries; histamine shows the vasoconstrictive effect on both brain and mesenteric arteries; and the vasoconstrictive effect mainly produces via Ca²⁺ inflax.

Key words: histamine, diphenhydramine, cimitidine, nifidipine, artery