No production in cultured equine cells stimulated by LPS and cytokines

Abstract

Culture cells from a horse were stimulated by LPS and cytokines, and nitric oxide, (NO) production was rendered detectable by a fluorescent measurement reagent. Increase of NO production was observed over time in the LPS- and cytokine-stimulated cells after the addition of L-arginine, a substrate for NO. NO production was observed to increase slightly over time, even in cells not stimulated by the addition of L-arginine. The addition of L-NMMA (an i-NOS inhibitor) along with L-arginine to the LPS- and cytokine-stimulated cells was found to markedly suppress NO synthesis. Enhancement of fluorescence intensity depended on LPS levels, suggesting that NO production may also depend on LPS levels.