title: Occurrence of inhibitory histamine H2-receptors in isolated pulmonary blood vessels of dogs and rats.
abstract: Isolated, helically cut strips of pulmonary arteries and veins of dogs, and pulmonary arteries of rats, precontracted with norepinephrine or 5-HT exhibited potent concentration-dependent relaxations to impromidine and dimaprit (histamine H2-agonists). The occurrence of inhibitory histamine H2-receptors in the pulmonary vasculature could play a modulatory role in hypoxic pulmonary vasoconstriction.
mesh_terms: D000818:Animals; D017259:Dimaprit; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D006146:Guanidines / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D017446:Impromidine; D008297:Male; D008785:Metiamide / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D011651:Pulmonary Artery / Q000502:physiology*; D011667:Pulmonary Veins / Q000502:physiology*; D051381:Rats; D011968:Receptors, Histamine / Q000502:physiology*; D011970:Receptors, Histamine H2 / Q000187:drug effects / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology; D013890:Thiourea / Q000494:pharmacology
chemical_list: D006146:Guanidines; D007093:Imidazoles; D011968:Receptors, Histamine; D011970:Receptors, Histamine H2; D012701:Serotonin; D008785:Metiamide; D017446:Impromidine; D013890:Thiourea; D009638:Norepinephrine; D017259:Dimaprit