Abstract
Effects of nicotinic acid on glucose metabolism were studied in a series of experiments with goats. Oral administration of single doses of nicotinic acid (6.5-17.0 g) elevated blood glucose, impaired glucose tolerance and elevated insulin. The magnitude of the effects was related positively to nicotinic acid dosage. Maximum effect occurred 2-3 days after administration. Blood glucose was elevated with or without glucose administration despite markedly elevated insulin. Exogenous insulin given 48 h after nicotinic acid still reduced blood glucose although the response was delayed and was less than in control animals. A lactating cow given 160 g nicotinic acid exhibited alterations in glucose metabolism similar to control animals. Nicotinic acid, in addition to previously reported effects on lipid metabolism, has significant effects on carbohydrate metabolism.