Cutaneous vascular histamine H1 and H2 receptors in the guinea-pig: the histamine skin wheal as a cutaneous vascular model.
The roles of histamine H1 and H2 receptors in histamine skin wheals were studied in the guinea-pig. Intradermal injections of histamine, 0.125--2 micrograms/0.1 ml, produced wheals in a dose dependent manner. Pyrilamine maleate (3.2 mg/kg p.o., pretreatment for 1 hour) produced a dose dependent shift of the histamine wheal dose-response curve to the right in a parallel fashion. Metiamide, 3, 10 or 30 mg/kg p.o., had no effect on the histamine dose-response curve. However, a combination of metiamide (10 or 30 mg/kg) and pyrilamine (3.2 mg/kg) further increased the effect of pyrilamine. It is concluded that both H1 and H2 receptors are involved in histamine-induced wheals in the guinea-pig.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D008785:Metiamide / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D011968:Receptors, Histamine / Q000502:physiology*; D011969:Receptors, Histamine H1 / Q000502:physiology*; D011970:Receptors, Histamine H2 / Q000502:physiology*; D012867:Skin / Q000098:blood supply*; D012882:Skin Tests
D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D008785:Metiamide; D006632:Histamine; D011738:Pyrilamine