Metabolism of a glutathione conjugate of 2-hydroxyoestradiol by rat liver and kidney preparations in vitro.
Metabolism of a glutathione conjugate of 2-hydroxyoestradiol by rat liver and kidney preparations in vitro.
复制标题
大鼠肝脏和肾脏制剂对 2-羟基雌二醇的谷胱甘肽缀合物的体外代谢。
作者：
J. Elce
将成年雄性大鼠肝脏和肾脏制备物与（2-羟基雌二醇-1-基）[（35）S]谷胱甘肽孵育。谷氨酸和甘氨酸残基被肾脏微粒体组分中存在的酶去除;肝脏制备物无影响。所得2-羟基雌二醇-半胱氨酸缀合物在α-氨基上被乙酰辅酶A强化的肝和肾匀浆乙酰化，但在不存在该辅酶的情况下，或被肝或肾切片乙酰化不显著。这些结果表明，雌激素-谷胱甘肽结合物，如果在体内形成，将转化为相应的巯基尿酸排泄前。
Adult male rat liver and kidney preparations were incubated with (2-hydroxyoestradiol-1-yl)[(35)S]glutathione. The glutamic acid and glycine residues were removed by enzymes present in the kidney microsomal fraction; the liver preparations had no effect. The resulting 2-hydroxyoestradiol-cysteine conjugate was acetylated at the alpha-amino group by both liver and kidney homogenates fortified with acetyl-coenzyme A, but not significantly in the absence of this coenzyme, or by liver or kidney slices. These results suggest that an oestrogen-glutathione conjugate, if formed in vivo, would be converted into the corresponding mercapturic acid before excretion.