ENDOGENOUS NITRIC-OXIDE INCREASES PROSTAGLANDIN BIOSYNTHESIS IN CARRAGEENAN RAT PAW EDEMA

The influence of endogenous nitric oxide (NO) on prostaglandin biosynt hesis in rat carrageenin oedema was studied. Oedema formation and pros taglandin E(2) generation in the inflamed paw were both increased by L - but not D-arginine and reduced by the NO synthase inhibitor, L-N-G-n itro arginine methyl ester, and the NO scavenger, haemoglobin. Methyle ne blue, an inhibitor of the soluble guanylate cyclase, had no effect. These results suggest that endogenous NO modulates carrageenin oedema by increasing prostaglandin biosynthesis at the inflammatory site thr ough a cGMP-independent mechanism.