BACKGROUND: The key point in the treatment of acute cerebral infarction lies in inproving the blood supply of brain effectively as soon as possible as well as rescue ischemic and half diazonal nerve cells, so as to contract the local of infarction as great as possible.OBJECTIVE: To observe the effect of traditional treatment of cerebral piamatral microcirculation in gerbil with cerebral ischemic reperfusion injury by supplementing qi and activating blood circulation.DESIGN: Contrast animal experiment at random.SETTING: Zhabei Branch of Shanghai Changzheng Hospital.MATERIALS: The experiment was performed in the Institute of Naval Medicine (key laboratory of the whole army). Twenty-two healthy Monglian gerbils of clean grade (six months old) were selected and randomly divided into medicine group and control group with 11 gerbils in each group.METHODS: Animals were routinely anaesthetized and fixed in prone position to open the cranium window in median line and expose the pia mater. The cranium window was protected by being covered with a cotton ball containing artificial cerebrospinal fluid (ACSF) after operation. Gerbils were fixed in dorsal position with an median incision made in the lateral cervical nucleus to isolate and expose bilateral common carotid artery (CCA). The bilateral CCA were occluded by atraumatic micro-bulldog clamp, and the occluded blood flow in the distal end was observed under the microscope. Thirty minutes after occlusion of bilateral CCA, the vascular clamp was unclamped to recover the cerebral blood reperfusion. Gerbils in the medicine group were abdominally injected with 0.4 mL of Huangqi injection (containing 0.8 g of crude drug), 0.3 mL of compound Danggui injection (containing Danggui, Chuanqiong and Honghua, 0.09 g for each)and 0.3 mL of Danshen injection (containing 0.45 g of Shengyao). Animals in the control group were abdominally injected with same-volume of normal saline. The changes of pial microcirculation were quantitatively observed in two groups through cranium window respectively before blockage, at the reperfusion after blockage as well as in 120 minutes after injection by laser microcirculation microscope and the TV video system.MAIN OUTCOME MEASURES: The changes of piamatral microcirculation as well as comparison in venous blood flow velocity in gerbils of each group before and after ischemic reperfusion.RESULTS: All gerbils were involved in the analysis of results with no animal died in the experiment.①When the CCA of animals in the two groups were blocked, obvious contraction of piamatral microcirculation was seen and partial blood vessels were blocked up. Platelet and red blood cells etc.adhered to the arteriolae of grade Ⅰ and veinules below grade Ⅲ with microthrombus formed and large ischemic area appeared. The blood flow rate was obviously slowed down. Moderate and severe aggregations were found in red blood cells, and the white blood cells were significantly increased.There was obvious exudation in the periphery of microvessels. After CCA reperfusion, the arteriolae and veinule were in different thickness, and the thrombus in veinule of grade Ⅰ and Ⅱ formed in the cerebral ischemia were difficult to be removed by blood flow. Red blood cell moderately aggregated, and the number of white blood cells greatly increased. White small thrombus could be seen sometimes, while the exsudation in the periphery of microvessel was not significantly ameliorated. Great changes were found in gerbils of the medicine group after abnormal injection of supplementing qi and activating blood circulation medicine: almost all arteriolae and venulae were opened, and the rate of blood flow was accelerated with the blood flow rate remarkably increased. Deposit in the venulae began to decreased, and the thrombus was gradually dissolved. Red blood cells were moderately aggregated or normal. Blood flow in ischemic spot was improved significantly than that after reperfusion. The exudation in the periphery of microvessels was gradually lessened even dissolved. However,no obvious change was found in gerbils of the control group. ②The blood flow rate of arteriole in the medicine group was 1.04-1.50 mm, which was obviously higher than that in the control group with significant differences (P ＜ 0.5-0.01).③The blood flow rate of veinule in the medicine group was 0.96-1.12 mm/s, which was remarkably higher than that in the control group with marked differences (P ＜ 0.05-0.01).CONCLUSION: The effect on piamatral microcirculation of gerbil with cerebral ischemic reperfusion by supplementing qi and activating blood is exact, which is directly related with accelerated blood flow rate, expanded veinule and arteriolae as well as ameliorated blood-supply of brain.