Abstract

5-Methylpyrazole-3-carboxylic acid stimulated the incorporation of labeled glucose into adipose tissue in vivo without stimulating the incorporation of labeled glucose into glycogen of the diaphragm and without increasing the glucose turnover of normal rats to any significant degree. Nicotinic acid shared with 5-methylpyrazole-3-carboxylic acid these effects on adipose tissue metabolism. 5-Methylpyrazole-3-carboxylic acid blocked the rise of the plasma free fatty acids and partially prevented the rise of the blood sugar in acutely insulin-deficient rats due to the maintenance of a normal utilization of glucose by the tissues (muscle) despite insulin deficiency. After prolonged treatment with 5-methylpyrazole-3-carboxylic acid an escape phenomenon was observed. 5-Methylpyrazole-3-carboxylic acid still acutely depressed the level of free fatty acids, but the effect was short lived. 5-Methylpyrazole-3-carboxylic acid stimulated incorporation of glucose into glycerides of adipose tissue more markedly and more rapidly in pretreated than in normal rats, but the fatty acids and glycerides synthesized from glucose left the tissue again more rapidly.