Abstract: 【Abstract】 Objective We used ischemic preconditioning method by blocking rabbit’s right carotid artery at intervals repeatedly while increasing blocking time so that collateral circulation in brain was reconstruction. We observed the cerebral protection after the right carotid artery was permanently blocked. Methods 48 rabbits were randomly divided into experimental and control groups, n = 24. The right common carotid artery of the animals in the experimental group was compressed. We blocked the right carotid artery blood flow by the Inflatable balloon, ischemic time = number of times× 5 + 40 (min), 2 times per day. The longest blocking lasted 4h(20th days). The control group was the same as the experimental group, except that the carotid artery blood flow was not blocked. The establishment of a right collateral circulation in the rabbit brain was observed with Digital Subtraction Angiography (DSA) on the 1st, 10th and 20th day respectively. The blood flow in the right common carotid artery was completely blocked at 20th day. The neurological deficit score was observed at 1、3、6、24h. Then we got brain tissue specimens and compared the brain water content and pathological changes between the two groups. The number of brain microvascula of the corresponding places was also counted Conclusions during the experiment, no abnormal behaviors such as excitement, agitation, lethargy and et al were observed in either group. DSA showed that contrast medium passed into the right middle cerebral artery Willis ring on the 10th day. Compared with the 1st day, the blood vessels on the right side were much clearer in DSA. On the 20th day there was almost no difference between the left and right sides in vascular imaging. Experimental group’s neurological deficit score and water content were lower than those of the control group’s(P < 0.05). Observation showed that there were more brain microvascular the right side (ischemic side) pathological specimens of the experimental group (5. 3 ±0. 5) than control group(3. 5 ±0. 4) (P < 0.05) under microscope at 400 times. Results By multiple ischemic preconditioning cerebral artery Willis ring and cerebral collateral circulation would be reconstruct, and it had obvious protective effect on cerebral ischemia resulted from completely blocked carotid arteries.
【Key words】ischemic preconditioning; collateral circulation; neurological deficit score; cerebral ischemia
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