Novel Role Found for Calcium Channels in Pacemaker Cell Function

New research has uncovered a previously unclear link between the autorhymic function of pacemaker cells and critical interaction between calcium channels and ryanodine-receptor mediated calcium signalling. The study compared the pacemaker cells of normal and mutated rats which lacked L-type Cav1.3 channels. The mutant rats were not able to handle calcium as well, and had a lesser rate of cardiac contraction. These rats also had less regulation of ryanodine-receptor dependent calcium release in the diastolic phase. The release of calcium in sinoatrial cells was found to be heavily controlled by calcium ion channels (Cav1.3). The mutant mice suffered from bradycardia, other arrhythmias and heart failure at a higher rate than the control mice. The Cav1.3 channels have also been linked to pancreatic beta-cell stimulation for insulin release and are pacemaker channels in the CNS. The isolation of Cav1.3 channels and their link to pacemaker regulation are bring taken into account by pharmaceutical companies and incorporated into cardiac drug therapies.

I found this article interesting because we talk about intracellular calcium quite a bit in class, and this is a real-life example of the importance of IC calcium. Also since I plan to be a cardiologist, this information is interesting because it is a breakthrough in cardiovascular research, which will be important to me when I am a practicing cardiologist.

http://www.sciencedaily.com/releases/2011/03/110309112856.htm