Effect of nicotinic acid on cerebroside synthesis in rat brain

The effect of nicotinic acid on the synthesis of cerebrosides in the brain was studied during brain development. The concentration of cerebrosides in the brain was significantly lower in nicotinic acid-deficient animals than in those receiving a nicotinic acid-supplemented diet. The total lipid concentration in the brain of nicotinic acid-deficient rats was slightly lower than that of rats fed on the nicotinic acid-supplemented diet. Therefore, the ratio of cerebrosides to total lipids of nicotinic acid-deficient rats was markedly lower than that of nicotinic acid-supplemented rats. However, this low cerebroside level in nicotinic acid-deficient rats was restored by the administration of the nicotinic acid-supplemented diet. Synthesis of cerebrosides was followed in the brain of developing rats after intracerebral injection of L-[U]14C]serine. The total amount of radioactivity incorporated into the cerebroside fraction of nicotinic acid-deficient rat was smaller than that of nicotinic acid supplemented rats. These observations suggest that nicotinic acid affects cerebroside synthesis in the brain of rats.