Smits G A, Jap P H, Heerschap A, Oosterhof G O, Debruyne F M, Schalken J A
Department of Urology, University Hospital Nijmegen, The Netherlands.
Ultrasound Med Biol. 1993;19(5):399-409. doi: 10.1016/0301-5629(93)90059-w.
To investigate the in vivo effects of electromagnetically generated high energy shock waves (HESW) on skeletal muscle, we used in vivo 31P nuclear magnetic resonance (NMR) spectroscopy (MRS) measurements and correlated the results with microscopical studies. Mouse skeletal muscle (calf muscle) was exposed to 200 or 800 HESW (Pmax: 37.5 MPa, Pmin: 5.2 MPa, tr: 30-120 ns, tw: 340 ns, frequency: 1.25 Hz). In the 31P MRS spectra, transient alterations were observed. A prominent increase of inorganic phosphate (Pi) peaks was found, as well as the appearance of Pi with different chemical shifts, reflecting the presence of different pH values (5.4-7.1) in cellular or tissue compartments. Within 20-96 h after exposure, pH values and Pi levels returned to normal. The changes were more pronounced in the animals treated with 800 HESW as compared to 200 HESW. Light and electron microscopy demonstrated focal degenerations of muscle fibers. This process consisted of disorganization of myofilaments and structural changes in sarcoplasmic organelles and was progressive in time. The (ultra)structural changes were not present in all myofibers (i.e., between affected degenerating fibers unaffected intact fibers were seen). Several ultrastructural abnormalities were also found in capillaries even up to severe dilatation and disruption, as well as in the peripheral nerves. The degeneration of the preexisting myofibers was predominantly confined to type 1 fibers and was followed by a regeneration of the muscle tissue by proliferation of myoblasts. A notable amount of myotubes still showed vacuolization. We conclude that in vivo HESW exposure of skeletal muscle tissue results in a degeneration of myofibers. The cellular effects are present in foci and associated with changes in the 31P NMR spectra. The NMR spectroscopy technique provides us with a noninvasive method to evaluate in a longitudinal way the biological effects of HESW.
为了研究电磁产生的高能冲击波（HESW）对骨骼肌的体内效应，我们采用了体内31P核磁共振（NMR）波谱法（MRS）测量，并将结果与显微镜研究相关联。将小鼠骨骼肌（小腿肌肉）暴露于200或800次HESW（Pmax：37.5MPa，Pmin：5.2MPa，tr：30 - 120ns，tw：340ns，频率：1.25Hz）。在31P MRS谱中，观察到了瞬态变化。发现无机磷酸盐（Pi）峰显著增加，以及具有不同化学位移的Pi的出现，这反映了细胞或组织区室中不同pH值（5.4 - 7.1）的存在。在暴露后20 - 96小时内，pH值和Pi水平恢复正常。与200次HESW处理的动物相比，800次HESW处理的动物中变化更明显。光学和电子显微镜显示肌纤维有局灶性变性。这个过程包括肌丝的紊乱和肌浆细胞器的结构变化，并且随时间进展。（超）结构变化并非存在于所有肌纤维中（即，在受影响的变性纤维之间可见未受影响的完整纤维）。在毛细血管中甚至发现了一些超微结构异常，直至严重扩张和破坏，在周围神经中也有发现。先前存在的肌纤维变性主要局限于1型纤维，随后通过成肌细胞增殖实现肌肉组织的再生。相当数量的肌管仍显示有空泡化。我们得出结论，骨骼肌组织在体内暴露于HESW会导致肌纤维变性。细胞效应存在于病灶中，并与31P NMR谱的变化相关。NMR波谱技术为我们提供了一种非侵入性方法，以纵向方式评估HESW的生物学效应。
