[Changes in Na, K-ATPase activity following adrenoreceptor blockade].

A regulatory factor released from the effector cell during blockade of postsynaptic alpha- and beta-adrenoreceptors with phentolamine and propranolol (5 X 10(7)-1 X 10(-6) M) and activating norepinephrine neuronal uptake and synthesis, was shown to activate, Na, K-ATPase of the rat isolated organs as well as the preparation of partly purified Na, K-ATPase extracted from the rat brain. Ouabain (1 X 10(-3) M) eliminated completely the activating effect of the regulatory factor on the ATPase.