ABSTRACT
Activities of cytidine 5'-diphosphate-choline glycerol choline phosphotransferase and uridine 5'-diphosphate galactose-ceramide galactosyltransferase were determined in isolated myelin in different brain regions of control, and rats with restricted food intake. Kinetic experiments indicated an increase in Km value of phosphocholinetransferase in brain stem of undernourished rats, without significant change in the specific activity of this enzyme. Stimulation of this myelin bound enzyme activity was also evident in the animals when myelin was treated with the detergent: Tween CF. 54. Though specific activities of galactosyl transferase in myelin of undernourished rats were significantly diminished, the Km of this enzyme was unaltered. These studies point to an adverse effect of early nutritional stress on the activities of enzymes bound to myelin membrane which has hitherto been considered metabolically inert.