Inducing effects of chronic administration of isoproterenol on 1-acyl-sn-glycero-3-phosphate and 1-acyl-sn-glycero-3-phosphocholine acyltransferases in rat parotid salivary gland.

Abstract

1. In rat parotid gland, chronic administration of isoproterenol caused significant increase of linoleic acid and decrease of arachidonic acid at the sn-2 position of phosphatidylcholine. 2. The activities of 1-acyl-sn-glycero-3-phosphate and 1-acyl-sn-glycero-3-phosphocholine acyltransferases were increased 3-8-fold and 2-fold, respectively, in the parotid gland microsomes of isoproterenol-treated rat. 3. Furthermore, the specificity of these two enzymes for various acyl-CoAs was also changed by administration of isoproterenol. 4. The alteration of unsaturated fatty acid composition at the sn-2 position of phosphatidylcholine was at least in part due to the change of activity and substrate specificity of lysophospholipid acyltransferases.