Synergism between protein kinase C activator and fatty acids in stimulating superoxide anion production in guinea pig polymorphonuclear leukocytes

Abstract

Treatment of guinea pig polymorphonuclear leukocytes (PMNL) with various fatty acids elicited superoxide anion (O 2 −) production and an increase in intracellular Ca 2+ ([Ca 2+] i). Both responses, however, were seldom observed when PMNL were treated at lower concentrations. But, simultaneous addition of 1-oleoyl-2-acetylglycerol (OAG), a protein kinase C activator, caused an increase in O 2 − production even at the lower concentrations of fatty acids. In contrast to the synergism in O 2 − production, [Ca 2+] i remained at almost the basal level irrespective of the presence of OAG. Among saturated fatty acids, those with carbon numbers of 14 to 18 were most effective in stimulating O 2 − production in combination with OAG. Unsaturated fatty acids with a carbon number of 18 were almost equally effective irrespective of the number of double bonds.