Kishi M, Tanaka H, Seiyama A, Takaoka M, Matsuoka T, Yoshioka T, Sugimoto H
Department of Traumatology, Osaka University Medical School, Japan.
Am J Physiol. 1998 May;274(5):H1435-42. doi: 10.1152/ajpheart.1998.274.5.H1435.
Leukocytes have been shown to contribute to ischemia-reperfusion injury in skeletal muscle. Pentoxifylline (PTXF), a xanthine-derived phosphodiesterase inhibitor, has received recent attention because of its action on leukocytes. To clarify the effects of PTXF in reperfusion injury, we measured the resting transmembrane potential difference (Em) and evaluated postcapillary venule microcirculation using intravital microscopy in rat skeletal muscle during ischemia and reperfusion. The infrarenal aorta was clamped for 90 min and then reperfused for 60 min. Persistent depolarization of the resting Em was observed in an ischemia-reperfusion (IR) group and was significantly repolarized in a PTXF group during the reperfusion period. The tissue water content was significantly reduced in the PTXF group, although no difference was noted in the tissue lactate content. Flowing erythrocyte velocity and wall shear rate in the PTXF group were significantly higher than in the IR group during the reperfusion period but without significant differences in vessel diameter and hemoglobin oxygenation. Blood flow measured by laser-Doppler flowmeter was also significantly improved in the PTXF group. Furthermore, the adherent leukocyte count was significantly reduced in the PTXF group during this same period. These results indicate that PTXF attenuated reperfusion-associated membrane injury and tissue edema and that PTXF suppressed leukocyte adhesion and improved hindlimb blood flow during the reperfusion period.
白细胞已被证明会导致骨骼肌缺血再灌注损伤。己酮可可碱（PTXF）是一种黄嘌呤衍生的磷酸二酯酶抑制剂，由于其对白细胞的作用，最近受到了关注。为了阐明PTXF在再灌注损伤中的作用，我们在大鼠骨骼肌缺血和再灌注期间，使用活体显微镜测量了静息跨膜电位差（Em），并评估了毛细血管后微静脉的微循环。将肾下主动脉夹闭90分钟，然后再灌注60分钟。在缺血再灌注（IR）组中观察到静息Em持续去极化，而在再灌注期间，PTXF组的Em显著复极化。PTXF组的组织含水量显著降低，尽管组织乳酸含量没有差异。在再灌注期间，PTXF组的红细胞流速和壁剪切率显著高于IR组，但血管直径和血红蛋白氧合没有显著差异。PTXF组通过激光多普勒血流仪测量的血流量也显著改善。此外，在同一时期，PTXF组的黏附白细胞计数显著减少。这些结果表明，PTXF减轻了再灌注相关的膜损伤和组织水肿，并且PTXF在再灌注期间抑制了白细胞黏附并改善了后肢血流。
