The occurrence and metabolism of alkyl and alk-1-enyl ethers of glycerol in transplantable rat and mouse tumors.

Abstract

SUMMARY Thirteen transplantable animal tumors have been quantita tively analyzed for their glyceryl alkyl and alk-1-enyl ethers in the neutral lipid and phospholipid fractions. The data ob tained demonstrate that the quantity of glyceryl ethers in the neutral lipid fraction of tumors is significantly higher than that found in normal tissues. The amount of ether-linked phospholipids is also higher in tumors than in most normal tissues. Radioactivity from intraperitoneal injections of palmitic acid-l-14C was incorporated into both the ether-linked aliphatic moiety (13-25% of the total glyceryl ether diester activity) and the esterified fatty acids of glyceryl ether diesters isolated from Ehrlich ascites cells. Labeling of the glyceryl ether diesters also occurred when fatty alcohols-14C and triglycerides-14C were administered to mice bearing the ascites cells; radio activity from acetate-2-14C, glucose-14C, and 3H20 was not incorporated into the glyceryl ether diesters. The specific ac tivity of the triglycA©ride fraction was always higher than that of the glyceryl ether diesters found in Ehrlich ascites cells after injections of palmitic acid-l-14C. In similar experiments, the specific activities of the alk-1-enyl ethers were always higher than the specific activities of the alkyl ethers in the neutral lipid fraction, but these specific activities were essentially the same in the phospholipid fraction.