Swanson R A, Yu A C, Sharp F R, Chan P H
Neurology Service, Veterans Administration Medical Center, San Francisco, CA 94121.
J Neurochem. 1989 May;52(5):1359-65. doi: 10.1111/j.1471-4159.1989.tb09180.x.
Compounds known to affect glycogen metabolism in vivo or in cell-free preparations were used to investigate the regulation of glycogen content in intact astrocytes cultured from newborn rat cortex. Compounds were added with fresh medium to culture dishes, and astrocyte glucose and glycogen content determined 24 h later. Increasing the medium glucose concentration from 7.5 mM to 30 mM increased cell glycogen content 80%. Addition of 2-deoxyglucose or 3-O-methyl glucose (2.5-10 mM) also increased cell glycogen content, 50-100%, suggesting a regulatory rather than mass action effect of glucose on astrocyte glycogen content. The phosphorylase b inhibitors 2,2',4,4',5,5'-hexabromobiphenyl and riboflavin had no effect on astrocyte glycogen content, consistent with negligible phosphorylase b activity in normal astrocytes. Phenobarbital and L-methionine-DL-sulfoximine (MSO) are both known to induce astrocyte glycogen accumulation in vivo. The addition of phenobarbital (2 mM) had no effect on the glycogen content of cultured astrocytes, suggesting an indirect mechanism for the in vivo effect. MSO at 1 mM, however, induced a 300% increase in glycogen content. The time course of glucose and glycogen content after MSO administration suggests this increase to be the result of slowed glycogenolysis rather than accelerated glycogen synthesis.
已知在体内或无细胞制剂中影响糖原代谢的化合物被用于研究新生大鼠皮质培养的完整星形胶质细胞中糖原含量的调节。将化合物与新鲜培养基一起添加到培养皿中，并在24小时后测定星形胶质细胞的葡萄糖和糖原含量。将培养基葡萄糖浓度从7.5 mM增加到30 mM可使细胞糖原含量增加80%。添加2-脱氧葡萄糖或3-O-甲基葡萄糖（2.5 - 10 mM）也可使细胞糖原含量增加50 - 100%，这表明葡萄糖对星形胶质细胞糖原含量具有调节作用而非质量作用效应。磷酸化酶b抑制剂2,2',4,4',5,5'-六溴联苯和核黄素对星形胶质细胞糖原含量没有影响，这与正常星形胶质细胞中磷酸化酶b活性可忽略不计一致。苯巴比妥和L-蛋氨酸-DL-亚砜胺（MSO）在体内均已知可诱导星形胶质细胞糖原积累。添加苯巴比妥（2 mM）对培养的星形胶质细胞的糖原含量没有影响，这表明体内效应存在间接机制。然而，1 mM的MSO可使糖原含量增加300%。MSO给药后葡萄糖和糖原含量的时间进程表明，这种增加是糖原分解减慢而非糖原合成加速的结果。
