Histamine receptors in the skin melanophores of Indian bullfrog Rana tigerina.
Histamine and 2-methyl histamine caused dose-dependent aggregation of the integumental melanophores of Rana tigerina both in vitro and in vivo. The aggregating effects were antagonised by mepyramine and metiamide, specific H1 and H2 receptor blockers, respectively. Compound 48/80 and EDTA augmented the melanin-aggregating effects of exogenously applied histamine and 2-methyl histamine in in vivo experiments. 4-Methyl histamine, a specific H2 receptor agonist, dispersed the frog melanophores in in vitro studies, the dispersing effects were blocked by metiamide.
Ali
S A
SA
Post Graduate Zoology Department, Saifia College of Science and Education, Bhopal, India.
Peter
J
J
Ali
A S
AS
D000818:Animals; D004492:Edetic Acid / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D008543:Melanins / Q000378:metabolism; D008547:Melanophores / Q000187:drug effects / Q000378:metabolism*; D008761:Methylhistamines / Q000494:pharmacology; D008785:Metiamide / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D011898:Ranidae / Q000033:anatomy & histology / Q000378:metabolism*; D011968:Receptors, Histamine / Q000187:drug effects / Q000378:metabolism*; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D012880:Skin Pigmentation / Q000187:drug effects / Q000502:physiology; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology