Effects of acetylenedicarboxylate: relationship between decreased carcass lipid and increased liver size and lean body weight.

Potassium acetylenedicarboxylate, when administered in the diet, reduced the body lipid content of normal mice, genetically obese (ob/ob) mice, and their lean (+/?) littermates, and mice made obese by treatment with goldthioglucose. Food intake was unchanged in the lean mice but decreased in the obese mice. Carcass lipid was decreased in genetically obese mice compared to pair-fed controls. Oxygen consumption per mouse was increased in normal mice. The reduction in carcass lipid was not produced in normal mice that were dosed orally or were fed on a diet containing 55 per cent sucrose. Nor was it produced in male castrated mice or streptozotocin-treated mice that were given daily injections of insulin. The reduction in body lipid weight in lean mice was correlated with an increase in liver weight. Liver weight was not increased in genetically obese mice, but there was an increase in lipid-free dry weight. Weight gain was increased in lean mice and decreased in the obese mice compared to ad lib-fed controls. A red colouration of the skin developed in situations where body lipid content was decreased; plasma histamine was increased in lean mice. It is proposed that increased histamine synthesis leads to increased protein turnover and decreased body lipid content.