title: Effects of dihydroergotamine methanesulfonate on the microcirculation of the rat cremaster muscle.
abstract: Effects of dihydroergotamine on the microcirculation of the rat cremaster muscle were investigated microscopically using colour photographic technique. 1. Dihydroergotamine 10(-4) g/ml constricted arterioles of the rat cremaster. 2. Dihydroergotamine 10(-4) g/ml produced a significant contraction of venules. 3. Dihydroergotamine 10(-4) g/ml markedly inhibited the contractile response of noradrenaline 10(-6) g/ml on arterioles of the rat cremaster. The results suggest that dihydroergotamine has an appreciable vasoconstrictive action, especially upon venules, and that dihydroergotamine also has an adrenergic alpha-receptor blocking action. By means of highly sensitive negative colour film we obtained a satisfactory photograph of the rat cremaster's circulation.
mesh_terms: D000818:Animals; D001160:Arterioles / Q000187:drug effects; D004087:Dihydroergotamine / Q000494:pharmacology*; D008297:Male; D009132:Muscles / Q000098:blood supply*; D009638:Norepinephrine / Q000037:antagonists & inhibitors; D051381:Rats; D014661:Vasoconstriction / Q000187:drug effects; D014699:Venules / Q000187:drug effects
chemical_list: D004087:Dihydroergotamine; D009638:Norepinephrine