THE EFFECT OF ACUTE FEEDING OF CARNITINE, ACETYL CARNITINE AND PROPIONYL CARNITINE ON BASAL AND A23187-STIMULATED EICOSANOID RELEASE FROM RAT CARRAGEENAN-ELICITED PERITONEAL-MACROPHAGES

Little is known about the ability of carnitine to modulate cell functions. As carnitine plays an important role in lipid metabolism we investigated the acute effect of L-carnitine, L-acetyl carnitine and L-propionyl carnitine (300 mg/kg per d; 4 d) on the basal and calcium-ionophore (A23187)-stimulated release of arachidonic acid metabolites from rat carrageenan-elicited peritoneal macrophages. A decrease in the number of peritoneal carrageenan-elicited macrophages was observed after feeding all three compounds. The basal release of prostaglandin E2, 6 keto-prostaglandin Fl∞ and leukotriene B4 was stimulated by all treatments. In contrast, thromboxane B2 production was diminished by feeding carnitine and acetyl carnitine. A23187-stimulated synthesis of 6 keto-prostaglandin Fl∞ and leukotriene B4 was further enhanced by all three compounds. Acetyl carnitine and propionyl carnitine also enhanced thromboxane B2 synthesis. However, no effects on prostaglandin E2 formation were detected. The 6 keto-prostaglandin Fl∞:thromboxane B2 ratio, calculated from the basal and A23187-stimulated values, was increased by carnitine treatment. In the presence of A23187 there was also an increase in the 6 keto-prostaglandin Fl∞: leukotriene B4 ratio. We conclude that carnitine, and possibly some of its derivatives, could modify the macrophage component of an inflammation in vivo. Carnitine compounds: Peritoneal macrophages; Arachidonic acid metabolites: Rat. © 1990, The Nutrition Society. All rights reserved.