Changes in the fibrinolytic activity of blood flowing from the skeletal muscles during electrostimulation of the peripheral end of the cut-off sympathetic chain at the blockade of alpha-adrenoceptors have been studied in the acute experiments on cats. It is stated, that this action induces not only an increase of vascular conductivity but also fibrinolysis stimulation relating to the secretion of plasminogen activators to the blood. The effect of fibrinolysis stimulation was reproduced during intraarterial infusion of acetylcholine and was blocked by atropine. The vasodilating reactions on sodium nitroprusside and papaverine similar by intensity to the cholinergic reactions induce no plasminogen activator release. The existence of the specific regulation mechanism of plasminogen activator secretion, mediated by M-cholinoceptors is suggested.