High Ca content of pacemaker tissues in the frog heart

Yasuichiro FUKUDA
1984 The Japanese Journal of Physiology  
Cation contents of various cardiac regions were determined in the isolated perfused bullfrog heart. The Ca content was much higher in the pacemaker tissues (sinus venosus and atrio-ventricular ring muscle) than in the atrial or ventricular muscles even with extracellular Ca deficiency. A possible relationship between stored Ca and spontaneous pacemaker activity is discussed.
doi:10.2170/jjphysiol.34.1117 fatcat:c7433pdk6rfdlpbepfbww6fl7q