[Effects of glucosides on a spontaneously active vascular smooth muscle in vitro (author's transl)]

There is no support for the view that cardiac glucosides increase the resting tension in the rat portal vein, although such an effect on vascular smooth muscle might have been expected from the results of investigation on the coronary vessels. Glucosides in a concentration of 10(-4) m inhibit contractility while increasing the frequency of contractions. These changes of spontaneous activity are not accompanied by equivalent changes of the intracellular cation concentrations. There are no significant differences between the effects of g-strophanthine, k-strophanthoside and convallatoxin.