Fatty acid composition of submandibular salivary gland lipids in essential fatty acid deficient rats.

Essential fatty acid (EFA) deficiency was induced in young weanling rats by feeding a fat-free diet or a diet containing 7% Hydrogenated coconut oil (HCO). At intervals of 4, 8, and 16 weeks, rats from the deficient and the control groups were killed and their Submandibular Salivary Glands (SMSG) were dissected out and extracted for lipids. The fatty acid composition of total lipids, triglycerides (TG), free fatty acids (FFA), phosphatidyl choline (PC), and phosphatidyl ethanola-mine (PE) fractions was determined. The levels of 16:1 and 18:1 were increased whereas those of 18:2 and 20:4 were decreased in the EFA-deficient groups as compared to the controls. 5,8,11-eicosatrienoic acid (20:3 omega9) accumulated in the total lipids as well as other lipid fractions of the SMSG from the deficient rats. The levels of this fatty acid increased as the EFA-deficiency progressed. Changes in fatty acid composition of SMSG lipids of EFA-deficient rats were associated with a reduction in flow rate of whole saliva. Protein concentration and amylase activity of saliva was the same in the two groups.