Referenced in: none

Automatically associated channels: Cav2.1

Title: Modified autonomic regulation in mice with a P/Q-type calcium channel mutation.

Authors: Takayoshi Ohba, Eiki Takahashi, Manabu Murakami

Journal, date & volume: Biochem. Biophys. Res. Commun., 2009 Mar 27 , 381, 27-32

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/19351589

Abstract
Recent genetic analyses revealed an important association between P/Q-type channels and hereditary neurological disorders. The alpha1 subunit of P/Q-type channels is coded by a single CaV2.1 gene. Since calcium entry via neuronal calcium channels is essential for neurotransmission, P/Q-type channels may play an important role in cardiac autonomic neurotransmission. To elucidate the physiological importance of P/Q-type channels in autonomic nerve control, we used rolling Nagoya (tg(rol)) mice, which have a mutation in the CaV2.1 gene and decreased P/Q-type channel currents with reduced voltage sensitivity. The tg(rol) mice demonstrated unmodified expression of other calcium channel subunits. Electrocardiogram and echocardiographic analyses revealed decreased heart rate. Furthermore, omega-agatoxin IVA, a P/Q-type channel inhibitor, decreased heart rate and ejection fraction only in wild-type mice, thus suggesting a significant involvement of P/Q-type channels in chronotropic regulation. Atrium contraction analyses revealed a minor but significant role for P/Q-type channels in sympathetic and parasympathetic nerve regulation.