Vendemiale G, Palmieri V, Palasciano G, Altomare E
Dept. of Internal Medicine, University of Bari, Italy.
Scand J Gastroenterol. 1994 Nov;29(11):1034-8. doi: 10.3109/00365529409094882.
Since the effect of exogenous glutathione (GSH) on overall hepatic GSH homeostasis is not known, the present study investigated the changes in the hepatic, biliary, and plasmatic GSH levels during GSH administration in intact rats.
An exteriorized biliary-duodenal fistula was established, and GSH (1 mmol/kg over 2 h) or saline was administered intraperitoneally to rats with or without pretreatment with 5 mmol/kg L-serine borate, an inhibitor of gamma-glutamyltransferase (GGT).
Three hours after GSH administration, biliary GSH efflux and bile flow rose from 104.7 +/- 5.6 to 290.6 +/- 8.6 micrograms/ml bile and from 20.2 +/- 1.3 to 30.2 +/- 2.1 microliters/min, respectively; GSH-treated rats also showed increased liver (35%) and posthepatic vein plasma (68%) GSH concentrations compared with controls. By contrast, in rats pretreated with the GGT inhibitor GSH administration appeared to be devoid of any effect, except for a modest biliary GSH increase.
This study indicates that significant changes occur in the hepatic GSH homeostasis after intraperitoneal GSH administration. The activity of hepatic GGT, most likely through degradation of circulating GSH, followed by an increase in cysteine availability, seems to account, at least partially, for the reported effects.
由于外源性谷胱甘肽（GSH）对肝脏整体谷胱甘肽稳态的影响尚不清楚，本研究调查了完整大鼠在给予GSH期间肝脏、胆汁和血浆中谷胱甘肽水平的变化。
建立体外胆管十二指肠瘘，对γ-谷氨酰转移酶（GGT）抑制剂L-丝氨酸硼酸盐预处理或未预处理的大鼠腹腔注射GSH（2小时内1 mmol/kg）或生理盐水。
给予GSH 3小时后，胆汁中GSH流出量和胆汁流量分别从104.7±5.6微克/毫升胆汁增加到290.6±8.6微克/毫升胆汁，从20.2±1.3微升/分钟增加到30.2±2.1微升/分钟；与对照组相比，给予GSH的大鼠肝脏（35%）和肝后静脉血浆（68%）中的GSH浓度也有所增加。相比之下，在接受GGT抑制剂预处理的大鼠中，给予GSH似乎没有任何作用，除了胆汁中GSH略有增加。
本研究表明，腹腔注射GSH后肝脏谷胱甘肽稳态发生了显著变化。肝脏GGT的活性，很可能是通过降解循环中的GSH，随后半胱氨酸可用性增加，似乎至少部分解释了所报道的效应。
