[Effect of streptozotocin diabetes on the in vivo conversion of gamma-linolenic and dihomo-gamma-linolenic 14C acids to arachidonic acid in the rat kidney and in the rat body].

Streptozotocin diabetic rats were administered the same tracer dose of either [1 14C] gamma-linolenic acid or [2 14C] dihomo-gamma-linolenic acid by stomach tube seven days after streptozotocin injection. They were killed 48 hours later and the radioactivity in individual fatty acids of the kidneys and the whole animal determined by radio-gas chromatography. Results were compared to those obtained in non diabetic rats similarly prepared. With either radioactive precursor, 14C radioactivity incorporated into arachidonic acid, only as specific radioactivity of this acid, were considerably decreased in diabetic rats compared with normal rats, while the weights of renal and whole rat arachidonic acid were the same in the two groups of animals. These results suggest that, in vivo, streptozotocin diabetes causes a partial inhibition of the delta 5-desaturation of dihomo-gamma-linolenic acid, considered as a secondary step in linoleic acid metabolism, both in the kidneys and the whole rat as in the liver.