脑缺血再灌注损伤后超短波治疗最佳时机的选择

Choice of the best therapeutic occasion of ultrashortwave therapy after cerebral ischemia-reper fusion injury

目的:观察超高频电场-超短波对大鼠局灶性脑缺血再灌注损伤后脑水肿的影响以及最佳治疗时机。方法:实验于2004-06/10在中国医科大学附属第一医院理疗科实验室完成。①所用wistar大鼠共45只,随机分为6组:空白对照组(n=6)、对照组(n=8)和4个治疗组(n=31,立即治疗组、6h治疗组、12h治疗组和18h治疗组)。用线栓法制备各组大鼠一侧大脑中动脉栓塞-再灌注模型,造成大鼠右脑缺血2h再灌注24h。②治疗组分别于再灌注后立即、6h、12h、18h给予超短波治疗10min(频率为40.68MHz,最大输出功率为40W)。③空白对照组在造模中插线深度为1.0cm,不造成脑梗死;对照组于造模后给予超短波治疗处理过程但无输出。④采用Zea-Longa5级评分法评定神经功能缺损来筛选病例,剔除死亡及神经学评分为3,4级的大鼠,用干湿称重法测量符合实验标准的大鼠脑含水量,用苏木精-伊红染色光镜下观察形态学变化,比较各组大鼠脑含水量及病理学变化。结果:剔除死亡及神经学评分为3级和4级的大鼠9只,纳入结果分析的大鼠数量为36只,每组6只。①病理学观察结果:对照组病灶侧大脑半球体积明显增大,镜下可见神经元周围间隙明显增宽,核仁减小,浓缩甚至消失,血管腔内中性粒细胞增多明显。立即治疗组病理变化无减轻,而6,12,18h治疗组病灶侧可见中度或轻度水肿,血管腔内中性粒细胞增多轻微,病理损伤减轻。②脑含水量比较:对照组患侧脑含水量平均为(81.50±0.74)%,立即治疗组患侧脑含水量为(81.02±0.83)%,两组比较差异无显著性(q=1.53,P>0.05);6,12,18h治疗组患侧脑含水量分别为(79.78±0.70)%,(79.74±0.84)%和(79.39±1.06)%,均低于对照组,差异有显著性(q=5.49,5.61,6.73;P<0.05)。结论:超短波对大鼠局灶性脑缺血再灌注损伤具有神经保护作用,能减轻缺血侧脑含水量及病理改变,提示治疗最佳时机可能在再灌注6h后。

AIM： To observe the effects of ultra-high frequency electrical field-ultrashortwave on cerebral edema in rats after focal cerebral ischemia-reperfusion injury, and investigate the best occasion for the treatment. METHODS： The experiment was completed in the laboratory of Department of Physiotherapy, the First Affiliated Hospital of China Medical University from June to October 2004. ① Forty-five Wistar rats were randomly divided into six groups： blank control group （n=6）, control group （n=8） and four treatment groups （n=31, immediate treatment group, 6, 12 and 18-hour treatment groups）. The modals of unilateral focal cerebral ischemia in rats were produced with thread occlusion of the middle cerebral artery by 2-hour ischemia and 24-hour reperfusion. ② Rats in the four treatment groups were treated with ulrashortwave （the frequency was 40.68 MHz, the maximal output power was 40 W） for 10 minutes respectively at immediate, 6, 12 and 18 hours after reperfusion; The thread was inserted for 1.0 cm in the blank control group, so that the rats were not led to cerebral infarction; Rats in the control group received ultrashortwave treatment after model establishment without output. The rats were screened with neurologic impairment by the Zea-Longa 5-degree scoring, the dead ones and those with the score of grade 3 or 4 were deleted; The cerebral water content of rats met the experimental criteria was measured with the dry and wet weighing; The morphological changes were observed under light microscope with haematine-eosin staining; The water content and pathological changes were compared among the groups. RESULTS： Nine rats were deleted for death or neurological score of grade 3 or 4, and 36 rats were involved in the analysis of results with 6 rats in each group. ① Results of pathological observation： In the control group, the size of the focal cerebral hemisphere was obviously increased; Under light microscope, the interspaces around the neurons were obviously broadened, the nucleoli were decreased, shrank and even disappeared, and number of neutrophils in vascular lumen was obviously increased; The pathological changes were not relieved in the immediate treatment group, but moderate or mild edema was observed in the focal side of the 6, 12 and 18-hour treatment groups, and the number of neutrophils in vascular lumen was increased slightly, and pathological injuries were relieved. ② Comparison of water content： There was no significant difference in the average water content in the injured side between ＇the control group [（81.50±0.74）%] and immediate treatment group [（81.02±0.83）%] （q=1.53, P〉0.05）; It was significantly lower in the 6, 12 and 18-hour treatment groups [（79.78±0.70）%, （79.74±0.84）%, （79.39±1.06）%] than in the control group （q=5.49, 5.61, 6.73; P 〈 0.05）. CONCLUSION： Ulrashortwave has a neuroproteetive effect against focal cerebral isehemia-reperfusion injuries, and it can decrease the cerebral water content and relieve the pathological changes, it is indicated that the best occasion for the treatment is 6 hours after reperfusion.