Effect of histaminergic drugs on integumental melanophores of adult Bufo melanostictus.
Histamine and 2-methyl histamine caused dose-dependent aggregation of melanophores in toad B. melanostictus. The effects were effectively antagonised by mepyramine, a specific H1 histamine receptor antagonist, and metiamide a specific H2 receptor antagonist. On the other, hand 4-methyl histamine, a specific H2 receptor agonist dispersed the melanophores. The results suggest that adult Bufo melanophores have H1 histamine receptors which mediate melanophore aggregation, however, dispersion of melanophores may be controlled by undifferentiated histamine receptors of H2 type.
Peter
J
J
PG Zoology Department, Saifia Postgraduate College of Science and Education, Bhopal, India.
Ali
A S
AS
Ali
S A
SA
D000818:Animals; D002025:Bufonidae; D002449:Cell Aggregation / Q000187:drug effects; D006632:Histamine / Q000494:pharmacology; D018494:Histamine Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D008547:Melanophores / Q000187:drug effects* / Q000378:metabolism; D008761:Methylhistamines / Q000494:pharmacology; D008785:Metiamide / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology
D018494:Histamine Agents; D008761:Methylhistamines; D008785:Metiamide; C025566:4-methylhistamine; D006632:Histamine; C026259:2-methylhistamine; D011738:Pyrilamine