Wiechetek M, Garwacki S, Karlik W, Lewicki J, Souffrant W
Department of Pharmacology and Toxicology, Warsaw Agricultural University, Poland.
Arch Environ Contam Toxicol. 1993 Apr;24(3):375-80. doi: 10.1007/BF01128737.
The effect of three NaNO2 concentrations (0.5, 2.0, and 5.0 mM) on 15N-ammonia utilization, ureagenesis, glucose, pyruvate and lactate formation and glycogen breakdown were studied in isolated rat hepatocytes. Nitrite failed to affect the rate of glycogenolysis as well as the lactate and pyruvate formation, but at the same time it markedly increased the glucose formation. It is concluded that the increase in the glucose formation results from the nitrite stimulation of the rate of gluconeogenesis. An increased sodium nitrite concentration caused a significant decrease in the ammonia utilization and urea synthesis; there are strong linear correlations between the nitrite concentration and the amount of utilized ammonia (r = -0.93) and the formed urea (r = -0.96). The observed lower rate of ureagenesis in the presence of nitrite resulted from the diminished incorporation of the added 15N-ammonia into urea, as well as from the diminished urea formation from endogenous nitrogen. It is concluded that the disturbances in carbohydrate and nitrogen metabolism observed in the nitrite-poisoned animals are attributed to the direct effect of nitrite on metabolism.
研究了三种亚硝酸钠浓度（0.5、2.0和5.0 mM）对分离的大鼠肝细胞中15N-氨利用、尿素生成、葡萄糖、丙酮酸和乳酸生成以及糖原分解的影响。亚硝酸盐未能影响糖原分解速率以及乳酸和丙酮酸的生成，但同时它显著增加了葡萄糖的生成。得出的结论是，葡萄糖生成的增加是由于亚硝酸盐刺激糖异生速率所致。亚硝酸钠浓度升高导致氨利用和尿素合成显著降低；亚硝酸盐浓度与利用的氨量（r = -0.93）和生成的尿素量（r = -0.96）之间存在很强的线性相关性。在存在亚硝酸盐的情况下观察到的尿素生成速率降低是由于添加的15N-氨掺入尿素减少以及内源性氮生成尿素减少所致。得出的结论是，在亚硝酸盐中毒动物中观察到的碳水化合物和氮代谢紊乱归因于亚硝酸盐对代谢的直接作用。
