[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].
OBJECTIVE
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.


METHODS
Using whole cell patch-clamp technique, we quantitatively researched the ionic intensity and density of L-type Ca2+ channel (ICa-L).


RESULTS
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.


CONCLUSIONS
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.
Wang
Shu-yan
SY
Heart Center, Beijing Chao Yang Hospital, Capital Medical University, Beijing 100020, China.
Yang
Xin-chun
XC
Miao
Guo-bin
GB
Liu
Xiu-lan
XL
Zhang
Lin
L
D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D005260:Female; D006168:Guinea Pigs; D006333:Heart Failure / Q000276:immunology*; D008297:Male; D032383:Myocytes, Cardiac / Q000378:metabolism; D018408:Patch-Clamp Techniques; D011943:Receptors, Adrenergic, beta / Q000276:immunology*
D001323:Autoantibodies; D020746:Calcium Channels, L-Type; D011943:Receptors, Adrenergic, beta