Histamine effects on the 5-HT1c receptor expressed in Xenopus oocytes.
To analyze the cross-reactivity between serotonin (5-HT) and histamine, the in vitro transcribed RNA for the 5-HT1c receptor was functionally expressed in Xenopus oocytes. 5-HT significantly increased 45Ca2+ efflux in RNA-injected oocytes, but not in uninjected and water-injected control oocytes. Furthermore, histamine and the H1 receptor agonists, but not the H2 and H3 agonists, significantly induced 45Ca2+ efflux in 5-HT1c receptor RNA-injected oocytes, but not in uninjected and water-injected oocytes. However, the H1, H2, and H3 antagonists failed to inhibit histamine-induced 45Ca2+ efflux at 10(-6) M. This finding suggests that the 5-HT1c receptor can be activated by both 5-HT and histamine, although the action of histamine is different from classic histamine pharmacology.
Shichijo
S
S
Department of Medicine, University of California, San Francisco.
Payan
D G
DG
Harrowe
G
G
Mitsuhashi
M
M
D000818:Animals; D001679:Biogenic Amines / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002132:Calcium Radioisotopes; D003001:Cloning, Molecular; D005260:Female; D006632:Histamine / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D008845:Microinjections; D009865:Oocytes / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D011968:Receptors, Histamine / Q000187:drug effects; D011985:Receptors, Serotonin / Q000096:biosynthesis / Q000187:drug effects*; D014158:Transcription, Genetic / Q000502:physiology; D014982:Xenopus laevis
D001679:Biogenic Amines; D002132:Calcium Radioisotopes; D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D011968:Receptors, Histamine; D011985:Receptors, Serotonin; D012313:RNA; D006632:Histamine; D002118:Calcium