Iotti S, Lodi R, Gottardi G, Zaniol P, Barbiroli B
Dip. Medicina Clinica e Biotecnologia Applicata D. Campanacci, Università di Bologna, Italy.
Biochem Biophys Res Commun. 1996 Aug 5;225(1):191-4. doi: 10.1006/bbrc.1996.1152.
We used 31-phosphorus magnetic resonance spectroscopy to study in vivo the transport of inorganic phosphate (Pi) from cytosol into mitochondria as assessed by the kinetics of Pi recovery during ischemia after aerobic exercise in human skeletal muscle. In all subjects during the first 30 s of ischemia inorganic phosphate showed a marked decrease from the value measured at the end of exercise, whilst phosphocreatine maintained the same value reached at the end of exercise. Our results show that Pi transport from cytosol into mitochondria is active in the absence of ATP biosynthesis and lasts 30 s possibly as a consequence of a decreased pH gradient, due to symport of Pi and H+ associated with an inactive electron transport chain during ischemia.
我们采用31-磷磁共振波谱技术，通过有氧运动后人体骨骼肌缺血期间无机磷酸盐（Pi）恢复动力学来评估，对细胞溶胶中无机磷酸盐向线粒体的体内转运进行了研究。在所有受试者中，缺血的前30秒内，无机磷酸盐从运动结束时测得的值显著下降，而磷酸肌酸维持在运动结束时达到的相同值。我们的结果表明，在没有ATP生物合成的情况下，Pi从细胞溶胶向线粒体的转运是活跃的，并且持续30秒，这可能是由于缺血期间与不活跃的电子传递链相关的Pi和H+同向转运导致pH梯度降低的结果。
