PROSTAGLANDIN E(2) PRODUCTION IN SUBMANDIBULAR SALIVARY-GLANDS OF RATS IN ESSENTIAL FATTY-ACID DEFICIENCY

Three groups of rats were fed an essential fatty acid (EFA)-deficient diet (EFAD), marginally EFA-deficient diet (MEFAD) or a control diet. Arachidonic acid levels in total phospholipids and the ex-vivo production of prostaglandin E(2) (PGE(2)) in the presence of calcium ionophore were measured at 5 and 9 weeks in the submandibular salivary glands (SMSG). The arachidonic acid levels were significantly different among the 3 groups of rats fed the respective diets for 9 weeks. Ex-vivo PGE(2) production was significantly decreased in the EFAD group but not in the MEFAD group as compared to the control group. The changes in fatty acid composition, arachidonic acid levels and ex-vivo production of PGE(2) were reversed after 5 weeks of feeding the control diet to the EFAD or the MEFAD rats. Since arachidonic acid and PGE(2) are involved in signal transduction pathways in the SMSG, an EFA deficiency is likely to modify these pathways.