Kazuo H, Nishida T, Seiyama A, Ueshima S, Hamada E, Ito T, Matsuda H
First Department of Surgery, Osaka University Medical School, Suita, Osaka 565-0871, Japan.
Am J Physiol. 1998 Jul;275(1):H243-9. doi: 10.1152/ajpheart.1998.275.1.H243.
Hepatic tissue perfusion and O2 supply after ischemia are indispensable for recovery of cellular functions, but few studies have been performed regarding the recovery of tissue blood flow and O2 transport. After 5, 15, and 30 min of ischemia of rat livers, hepatic tissue perfusion, hepatic arterial and portal blood flow, plasma PO2, and O2 transport parameters were measured. Hepatic tissue blood flow and erythrocyte velocity in the sinusoids showed biphasic recoveries after temporal ischemia for 5, 15, and 30 min. The first peak in the flow appeared at 3-4 min after the initiation of tissue perfusion, and the second peak appeared at approximately 20 min, irrespective of the ischemic period. Hepatic blood flow during the initial increase contained relatively low O2-saturated blood compared with that in the second increase. Livers that had been subjected to a prior hepatic artery ligation only showed the first peak at approximately 4 min. The first increase in hepatic blood flow corresponded to the peak in the portal venous flow, and the second increase corresponded to that of the hepatic artery. These results suggested that hepatic microcirculation after temporary hepatic ischemia showed biphasic recoveries because of different restoration patterns of the portal vein and hepatic artery.
缺血后肝组织灌注和氧气供应对于细胞功能的恢复不可或缺，但关于组织血流和氧气运输的恢复情况，相关研究较少。在大鼠肝脏缺血5、15和30分钟后，测量肝组织灌注、肝动脉和门静脉血流、血浆氧分压以及氧气运输参数。在经历5、15和30分钟的暂时性缺血后，肝组织血流和肝血窦中的红细胞速度呈现双相恢复。血流的第一个峰值出现在组织灌注开始后的3 - 4分钟，第二个峰值出现在大约20分钟，与缺血时间无关。与第二次血流增加相比，初始血流增加时的肝血流中含氧量相对较低。先前接受过肝动脉结扎的肝脏仅在大约4分钟时出现第一个峰值。肝血流的第一次增加与门静脉血流的峰值相对应，第二次增加与肝动脉的峰值相对应。这些结果表明，暂时性肝缺血后的肝微循环呈现双相恢复，这是由于门静脉和肝动脉的恢复模式不同所致。
