Gaudio K M, Thulin G, Ardito T, Kashgarian M, Siegel N J
Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06510.
Am J Physiol. 1989 Sep;257(3 Pt 2):F383-9. doi: 10.1152/ajprenal.1989.257.3.F383.
A viable suspension of proximal tubules that had sustained an in vivo ischemic injury was harvested, and cellular integrity and viability were determined. The histopathological appearance of this preparation has characteristic features of an ischemic injury and ATP levels were comparable to those observed with nuclear magnetic resonance spectroscopy in vivo. Sprague-Dawley rats were subjected to 45 min of bilateral renal artery ischemia and the kidneys were allowed to reperfuse for either 15 min, 2 h, or 24 h before the harvest of the proximal tubule suspension. There was a decrease in base-line oxygen consumption from 34 +/- 0.8 nmol O2.min-1.mg protein-1 to 22 +/- 0.6 at 15 min of reflow. This decline in oxygen consumption persisted during the first 2 h of reflow and returned to control levels by 24 h. Residual respiration in the presence of ouabain was similar at all reflow intervals suggesting that the decrease in basal O2 consumption was related to decreased Na+-K+-ATPase in situ. In contrast, there was no significant difference in Na+-K+-ATPase activity when determined chemically under Vmax conditions in all experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)
收集经受了体内缺血性损伤的近端肾小管的活细胞悬液，并测定细胞完整性和活力。该制剂的组织病理学外观具有缺血性损伤的特征性表现，且三磷酸腺苷（ATP）水平与体内核磁共振波谱观察到的水平相当。对斯普拉格-道利大鼠进行45分钟的双侧肾动脉缺血处理，在收集近端肾小管悬液前，让肾脏再灌注15分钟、2小时或24小时。再灌注15分钟时，基线耗氧量从34±0.8纳摩尔氧气·分钟⁻¹·毫克蛋白⁻¹降至22±0.6。这种耗氧量下降在再灌注的前2小时持续存在，并在24小时时恢复到对照水平。在所有再灌注间隔时间，哇巴因存在时的残余呼吸相似，表明基础耗氧量的降低与原位钠钾ATP酶的减少有关。相比之下，在所有实验组中，在最大反应速度（Vmax）条件下化学测定时，钠钾ATP酶活性没有显著差异。（摘要截断于250字）
