Kida Y, Katz A, Lee A D, Mott D M
Clinical Diabetes and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, Phoenix, AZ 85016.
Biochem J. 1989 May 1;259(3):901-4. doi: 10.1042/bj2590901.
Activities of glycogen synthase (GS) and GS phosphatase were determined on human muscle biopsies before and after isometric contraction at 2/3 maximal voluntary force. Total GS activity did not change during contraction (4.92 +/- 0.70 at rest versus 5.00 +/- 0.42 mmol/min per kg dry wt.; mean +/- S.E.M.), whereas both the active form of GS and the ratio of active form to total GS decreased by approximately 35% (P less than 0.01). GS phosphatase was inactivated in all subjects by an average of 39%, from 5.95 +/- 1.30 to 3.63 +/- 0.97 mmol/min per kg dry wt. (P less than 0.01). It is suggested that at least part of the contraction-induced inactivation of GS is due to an inactivation of GS phosphatase.
在以2/3最大自主力量进行等长收缩前后，对人体肌肉活检样本测定糖原合酶（GS）和GS磷酸酶的活性。收缩过程中总GS活性未发生变化（静息时为4.92±0.70，收缩时为5.00±0.42 mmol/分钟每千克干重；均值±标准误），而GS的活性形式以及活性形式与总GS的比率均下降了约35%（P<0.01）。所有受试者的GS磷酸酶平均失活39%，从5.95±1.30降至3.63±0.97 mmol/分钟每千克干重（P<0.01）。提示收缩诱导的GS失活至少部分是由于GS磷酸酶失活所致。
