Effect of the positive sera of autoantibodies against the human beta1-adrenoceptor from patients with congestive heart failure on activity of L-type Ca2+ channel in guinea pig cardiac myocytes / 中国医学科学院学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of the positive sera of autoantibodies against the human beta1-adrenoceptor from patients with congestive heart failure on activity of L-Type Ca2+ channel in guinea pig cardiac myocytes.</p><p><b>METHOD</b>Using whole cell patch-clamp technique, we quantitatively researched the ionic intensity and density of L-type Ca2+ channel (ICa-L).</p><p><b>RESULTS</b>The beta-adrenocepter agonist isoprenaline increased the ICa-L peak intensity and density from (997.09 +/- 227.5) pA and (8.20 +/- 0.86) pA/pF to (2241.01 +/- 348.5) pA and (18.98 +/- 1.18) pA/pF, respectively (P < 0.01). The positive sera of autoantibodies against the beta1-adrenoceptor could also increase ICa-L peak intensity and density from (963.57 +/- 207.56) pA and (8.14 +/- 0.72) pA/pF to (1382.41 +/- 241.36) pA and (11.70 +/- 1.03) pA/pF (P < 0.01). Esmolol, a beta1-adrenoceptor antagonist blocked these effects of isoprenaline and autoantibodies.</p><p><b>CONCLUSIONS</b>Human cardiac positive sera of autoantibodies against the beta1-adrenoceptor has an isoproterenol-like effect on cardiac myocytes receptor. It may participate in the pathophysiologic process of cardiac myocytes.</p>