[Activity and properties of cycl AMP-dependent protein kinases in the gray substance of the rat brain in acute radiation injury].

It was shown that in conditions of acute radiation affection there was a decrease of 37% and 32% in activity of cyclic AMP-dependent protein kinases, isolated from cytosol of gray substance of rat brain cells and from the synaptic membranes solubilized by triton X-100, respectively. The activity of enzymes from the control and irradiated animals was maximum with similar concentration of 3':5'-AMP (10(-6) M) and pH (7.4) in Tris-HCl and HEPES-buffers. Histone H4 was shown to be the best substrate for both enzyme forms. Other substrates under study were phosphorylated to a lesser degree.