히스티딘-리치 $Ca^{2+}$ 결합 단백질에 의한 심실근세포 수축 및 $Ca^{2+}$ Transient의 조절

The histidine-rich $Ca^{2+}$ binding protein (HRC) is a $Ca^{2+}$ binding protein in the sarcoplasmic reticulum (SR). In this study, we examined whether the HRC is involved in the regulation of cardiac contraction and $Ca^{2+}$ signaling using HRC knock-out (KO) mouse ventricular myocytes. In field-stimulated single mouse ventricular myocytes, cell shortenings and $Ca^{2+}$ transients were measured using a video edge detection and a confocal $Ca^{2+}$ imaging, respectively. Compared with the wide-type (WT) myocytes, the magnitudes of cell shortenings were significantly larger in HRC KO cells (P