The role of nitric oxide in the metabolism of labeled glucose in isolated rat uterus. Influence of 17 beta-estradiol

The influence of nitric oxide (NO) on the production of (CO2)-C-14 from labeled glucose in uteri isolated from ovariectomized-estrogenized rats was studied. Nitroprusside, an NO donor (NP), 200 mu M increased the formation of labeled CO2 from [U-C-14]glucose. This effect was blunted by hemoglobin (Hb) 20 mu g/mL, an NO scavenger. The addition of N-monomethyl arginine (NMMA), an inhibitor of NO synthase decreased the stimulatory action of NP at 400 mM. Incubation of uterine strips in the presence of NP plus acetylsalicylic acid (ASA) 10(-4) M (a cyclooxygenase inhibitor), inhibited the stimulatory action of NP on glucose metabolism. PGE(2) (10(-7) M) added to the incubation medium containing NP and ASA reversed the effect of the inhibitor. Neither NP nor Hb nor NMMA modified the (CO2)-C-14 production from labeled glucose in uterine strips from ovariectomized rats. The addition of NP to the incubating medium increased PGE accumulation by uterine strips from rats treated with estradiol, but not in ovariectomized animals. These results suggest that NO exerts a positive influence on glucose metabolism and PGE synthesis in isolated rat uteri from estrogenized animals.