Chemical sympathectomy abolishes the increase in blood pressure of linoleic acid deficient fed rats induced by salt loading.

In previous experiments an altered PG biosynthesis as well as an increase in blood pressure, heart rate and plasma epinephrine could be found after a linoleic acid deficient diet compared with a linoleic acid rich diet in rats with a high salt intake. We injected rats with 200 micrograms 6-hydroxydopamine into the right and left cerebral ventricles 17 days before a four-week linoleic acid deficient diet (0.5 J% linoleic acid) and salt loading (1.5% NaCl). In these rats the elevation of blood pressure and plasma epinephrine compared with linoleic acid rich fed rats (13.3 J+ linoleic acid) was abolished and heart rate was reduced. PG biosynthesis in aorta and kidney medulla homogenate (PGE and PGF) and stomach fundus homogenate (6-Keto-PGF1 alpha) was not influenced by chemical sympathectomy, neither were the food and fluid intakes. We conclude that an enhanced adrenergic activity (via alterations in PG metabolism?) is involved in the blood pressure increase after a linoleic acid deficient diet under high salt intake.