[Effect of a physiological load on the metabolism and phosphorylation of cell membrane proteins in the rat brain].

The effect of intense motor activity (swimming) followed by signs of physiological stress, on biosynthesis and phosphorylation of membrane proteins from different brain cells (neurons, glia) and sections (cerebellum, brain stem) as well as from liver, involved a significant decrease of 14C-methionine and 32P-phosphate incorporation related, probably, to inhibition of the physiological function, in all the electrophoretic fractions of proteins. In membrane proteins of cortical cells (particularly neurons), on the contrary, there was an increase of biosynthesis and phosphorylation in all the fractions. This seems to reflect an activation of cortical neurons for adaptation purposes.