Ca-channel currents in isolated frog ventricular cells are increased by thrombin.
Effects of the proteolytic enzyme thrombin in the modulation of cardiac Ca-channel currents were examined in single ventricular cells from frog myocardium, using the whole-cell voltage clamp technique (1). Application of 3.8 . 10(-9) M thrombin to the bath increased the peak of the Ca-channel current by 84 +/- 35% (8 cells). Hirudin (31.10(-9)M), a specific thrombin inhibitor, blocked the thrombin-induced increase of this current. The increase in the current can be made responsible for the measured positive inotropic effects on frog heart of thrombin.
Albitz
R
R
Julius Bernstein Institute of Physiology, Martin Luther University, Halle, GDR.
Markwardt
F
F
Franke
T
T
Nilius
B
B
D000818:Animals; D015220:Calcium Channels / Q000187:drug effects*; D006352:Heart Ventricles; D006629:Hirudins / Q000494:pharmacology; D066298:In Vitro Techniques; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D011893:Rana esculenta; D013917:Thrombin / Q000494:pharmacology*
D015220:Calcium Channels; D006629:Hirudins; D013917:Thrombin