Possible involvement of amino acid transporters on S-nitroso-cysteine-induced inhibition of arachidonic acid release in PC12 cells.

Previously, we proposed that S-nitroso-cysteine (SNC) was incorporated via the L-type-like amino acid transporters in rat brain slices. In PC12 cells (rat neuronal cell line), SNC inhibited [(3)H]arachidonic acid (AA) release induced by mastoparan (wasp venom peptide). We investigated the involvement of amino acid transporters on SNC-induced inhibition of [(3)H]AA release in PC12 cells. SNC inhibited mastoparan-stimulated [(3)H]AA release in a concentration-dependent manner in normal Na(+)- and low Na(+)-containing buffer. The inhibitory effect of 0.6 mM SNC in low Na(+) buffer decreased by 10 mM L-leucine, L-phenylalanine, L-methionine and L-cysteine. In contrast, L-alanine, L-threonine, L-valine or L-isoleucine showed very limited effects. Addition of L-leucine and L-phenylalanine, but not L-alanine or L-valine, also decreased the inhibitory effect of SNC on ionomycin/Na(3)VO(4)-stimulated [(3)H]AA release in normal Na(+) buffer. These findings suggest that SNC is incorporated via the amino acid transporters and inhibits AA release in PC12 cells.