Fatty acid composition in 1,2-diacylglycerol of diabetic and insulin-treated diabetic rat hearts.

Elevated levels of 1,2-diacylglycerol (DG) have been observed in streptozotocin-induced diabetic and insulin-treated diabetic rat hearts. The fatty acid moieties of 1,2-DG are considered to be related to its ability to activate protein kinase C. Therefore, we determined the fatty acids of 1,2-DG by gas chromatography and compared them with those of triglycerides in the myocardium. The triglyceride content returned to control levels after 4 weeks of untreated diabetes followed by 4 weeks of insulin treatment. There was a significant difference in the fatty acid composition of triglycerides between diabetic and control rats. Insulin treatment also returned the fatty acids of triglycerides in diabetes to the profile observed in control rats. On the other hand, insulin treatment of the diabetic rats did not normalize 1,2-DG content and its fatty acid composition. Fatty acid analysis of 1,2-DG showed that its profile in insulin-treated diabetic rats was different from that of either control or diabetic rats, suggesting that insulin-induced 1,2-DG differs from that seen in cases of diabetes.