Abstract
The effect of nicotinic acid (NiA) on cerebroside synthesis in brain was studied with 8 weeks-old rats. In 62 days-old rats fed NiA deficient diet for last 50 days, the concentration of NiA and cerebroside in brain was significantly lower than those receiving NiA supplemented diet. NiA concentration in brain of the NiA deficient rat was recovered by the administration of NiA. However, cerebroside concentration was not recovered by the administration of NiA. The synthesis of cerebroside was followed in brain of 62 days-old rat after an intracerebral injection of (U-^<14>C)-L-serine. After myelination no remarkable difference of the total radioactivity incorporated into cerebroside fraction was observed by the administration of NiA to the NiA deficient rat. From these observations, it was suggested that cerebroside synthesis in brain after myelination was not affected by the administration of NiA.
