Effect of Ether-Soluble Fraction of Bile on Hepatic Glycogen Storage

Abstract

Mizuta and Ikegami 1 have reported the presence in cattle bile of an ether-soluble substance which promotes glycogen formation in the liver. We decided to repeat their experiments because the data presented are not convincing and the concept may possess significance.

Methods. We have conformed as closely as possible to the general experimental plan of the Japanese observers. Young adult rabbits were fed our standard stock diet for 2 weeks. They were then placed in a stock in a wire cage to prevent coprophagia and fasted for 72 hours. The animals were then given 2 or 4 g of glucose per kilo body weight slowly intravenously (10 minutes) and 30 minutes later were given the bile extract similarly. 2.5 hours later, the animals were given pentobarbital intravenously, which induces anesthesia immediately. The liver was frozen in situ with CO₂ within a minute. The frozen liver was crushed to powder and a weighed portion placed in 30% KOH, digested and analyzed for glycogen by Somogyi's method. The results were calculated and expressed as the percent of glycogen in the powder.

The extracts were made from freshly frozen cattle bile. One extract, A, was made by rendering the thawed bile slightly alkaline (pH 8.0), evaporating to dryness in vacuo at a low temperature for 24 hours, and extracting the powder with ether and removing the ether in vacuo. A second extract, B, was made by slightly acidifying the thawed bile (pH 4.0) with phosphoric acid, steam distilling for 6 hours, the distillate being extracted with ether and the ether removed in vacuo. A third extract, C, was made as in the first extract, A, except the thawed bile was slightly acidified (pH 4.0) with phosphoric acid.