Sensitivity of histamine H3 receptor agonist-stimulated [35S]GTP gamma[S] binding to pertussis toxin.
The effect of histamine H3 receptor-selective ligands on [35S]guanosine 5'-o-(gamma-thio)triphosphate ([35S]GTP gamma[S]) binding has been examined in rat cerebral cortical membranes. R alpha-Methylhistamine and N alpha-methylhistamine produced a concentration-dependent stimulation of [35S]GTP gamma[S] binding which was attenuated in the presence of the selective histamine H3 receptor antagonist thioperamide. In addition, treatment of brain membranes with pertussis toxin abolished the histamine H3 receptor agonist stimulated binding of [35S]GTP gamma[S]. These results provide the first evidence that histamine H3 receptors couple directly to a Gi/Go protein in mammalian brain.
Clark
E A
EA
Department of Physiology and Pharmacology, Queen's Medical Centre, Nottingham, UK.
Hill
S J
SJ
D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism*; D002927:Cimetidine / Q000031:analogs & derivatives / Q000494:pharmacology; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism*; D017442:Histamine Agonists / Q000494:pharmacology*; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008761:Methylhistamines / Q000494:pharmacology*; D037342:Pertussis Toxin; D011485:Protein Binding; D011738:Pyrilamine / Q000494:pharmacology; D011869:Radioligand Assay; D051381:Rats; D018100:Receptors, Histamine H3 / Q000187:drug effects*; D013462:Sulfur Radioisotopes; D010566:Virulence Factors, Bordetella / Q000378:metabolism*
D017442:Histamine Agonists; D006635:Histamine H2 Antagonists; D008761:Methylhistamines; D018100:Receptors, Histamine H3; D013462:Sulfur Radioisotopes; D010566:Virulence Factors, Bordetella; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D002927:Cimetidine; D037342:Pertussis Toxin; C023990:tiotidine; D011738:Pyrilamine; C048140:N-methylhistamine