MUSCLE METABOLISM DURING LACTATE INFUSION IN HUMAN PHOSPHOFRUCTOKINASE DEFICIENCY
MUSCLE METABOLISM DURING LACTATE INFUSION IN HUMAN PHOSPHOFRUCTOKINASE DEFICIENCY
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DOI：
10.1152/jappl.1993.74.3.1342
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发表时间：
1993-03-01
影响因子：
3.3
通讯作者：
LEWIS, SF
中科院分区：
文献类型：
--
作者：
BERTOCCI, LA;HALLER, RG;LEWIS, SF
研究了静脉输注乳酸钠（La）对肌肉高能磷酸盐代谢、pH、三名肌肉磷酸果糖激酶（PFK）缺乏症患者和三名健康受试者在最大努力节律性握力运动中的静脉流出物[NH3]（5秒的收缩与5秒的休息交替进行）进行3分钟。健康受试者与PFK-缺乏性别和最大握力的患者。记录力的产生，并在乳酸盐输注期间与无乳酸盐输注期间相匹配。P-31磁共振波谱被用来测量细胞内磷酸肌酸（PCr），正磷酸盐（P（i）），ATP，和pH值的运动前臂的指深屈肌。La输注对健康受试者或休息时的患者无影响。在健康受试者中，La输注对PCr的消耗没有影响; P（i），ADP或静脉流出物NH3的积累;或运动肌肉pH值的下降。相比之下，在PFK缺陷患者的运动期间，[PCr]更高，（17.9 +/- 1.9 vs. 13.1 +/- 1.4 mmol/kg）和[磷酸单酯]（11.4 +/- 1.3 vs. 6.5 +/- 1.4 mmol/kg），[P（i）]（9.2 ± 1.8 vs. 5.0 ± 0.7 mmol/kg），[ADP]（60.4 +/- 7.0 vs. 37.9 +/- 9.9 mumol/kg）和静脉流出物[NH3]（335 +/- 136 vs. 176 +/- 61 mM）在La输注期间低于对照条件（P < 0.05）。La输注对PFK缺陷患者细胞内[PCr]、[P（i）]、[磷酸单酯]、[ADP]和[NH3]的影响与外源性La通过绕过PFK处的酶阻断而增加活动肌肉中氧化磷酸化速率的假设一致。
We studied the effect of intravenous infusion of sodium lactate (La) on muscle high-energy phosphate metabolism, pH, and venous effluent [NH3] in three patients with muscle phosphofructokinase (PFK) deficiency and three healthy subjects during maximal-effort rhythmic handgrip exercise (5 s of contraction alternated with 5 s of rest) performed for 3 min. Healthy subjects were matched to PFK-deficient patients for gender and maximal handgrip strength. Force production was recorded and during lactate infusion was matched to that without lactate. P-31-magnetic resonance spectroscopy was used to measure intracellular phosphocreatine (PCr), orthophosphate (P(i)), ATP, and pH in the flexor digitorum profundus of the exercising forearm. La infusion had no effect on healthy subjects or patients during rest. In healthy subjects, La infusion had no effect on depletion of PCr; accumulation of P(i), ADP, or venous effluent NH3; or decline in pH in exercising muscle. In contrast, during exercise in PFK-deficient patients, [PCr] was higher (17.9 +/- 1.9 vs. 13.1 +/- 1.4 mmol/kg) and [phosphomonoester] (11.4 +/- 1.3 vs. 6.5 +/- 1.4 mmol/kg), [P(i)] (9.2 +/-1.8 vs. 5.0 +/- 0.7 mmol/kg), [ADP] (60.4 +/- 7.0 vs. 37.9 +/- 9.9 mumol/kg), and venous effluent [NH3] (335 +/- 136 vs. 176 +/- 61 mM) were lower (P < 0.05) during La infusion than in control conditions. The effects of La infusion on intracellular [PCr], [P(i)], [phosphomonoester], [ADP], and [NH3] in PFK-deficient patients are consistent with the hypothesis that exogenous La augments the rate of oxidative phosphorylation in active muscle by bypassing the enzymatic block at PFK.