Histamine H2-receptor in atrium: signal transduction and response.

We have examined the signal transduction for H2-receptor mediated positive chronotropic response of guinea-pig right atrium. Our results indicate that phospholipid methylation is rapidly induced by histamine acting on H2-receptor in guinea-pig right atrium and therefore plays a predominant role in the signal transfer of H2-receptor-mediated cyclic AMP generation to exert positive chronotropic effect of atrium, as well as GTP-binding protein activation.