单侧局灶性脑梗塞大鼠脑电非线性参数的变化

Changes in EEG nonlinear indexes induced by focal cerebral infarction in rats

目的评价大鼠单侧局灶性脑梗塞时脑电非线性参数：关联维数（D2）、近似熵（ApEn）、复杂度（Cx）的变化，以探讨其监测脑梗塞的准确性。方法健康成年SD大鼠24只，随机分为2组，每组12只，对照组行右侧颈内动脉分离、结扎，不阻塞大脑中动脉；脑梗塞组行右侧颈内动脉分离、结扎，线栓法阻塞右侧大脑中动脉。记录阻塞前（T0）、阻塞即刻（T1）、阻塞后5、15、30、60min（T2～5）时脑部正常区域（C3）和缺血区域（C4）的D2、ApEn、Cx。于次日观察大鼠行为学并取其全脑标本，光镜下行病理学检查。结果对照组各时点、脑梗塞组T0时C3、C4的脑电非线性参数差异均无统计学意义（P〉0．05）；与C3相比，脑梗塞组T1～5时C4的脑电非线性参数降低（P〈0．05）；与T0时相比，脑梗塞组T4，5时C4的脑电非线性参数降低（P〈0．05）；与对照组相比，脑梗塞组T0时脑电非线性参数差异无统计学意义（P〉0．05），T1～5时脑电非线性参数先升高后降低（P〈0．05）。结论大鼠局灶性脑梗塞后D2、ApEn、Cx下降，脑电非线性参数可监测局灶性脑梗塞。

Objective To investigate the changes in EEG nonlinear indexes-correlation dimension （D2 ） , approximate entropy （ApEn） and complexity （Cx） induced by focal cerebral infarction and examine the possibility of using EEG nonlinear indexes for cerebral infarction monitoring. Methods Twenty-four adult SD rats of both sexes weighing 250-300 g were randomly divided into 2 groups （ n = 12 each） ： A focal cerebral infarction group in which right middle cerebral artery was occluded and B control group in which sham operation was performed. D2 , ApEn and Cx were recorded in parietal area at C3 （normal region） and CA （ischemic region）, before infarction （baseline） and immediately and at 5, 15, 30, 60 rain after infarction in both groups. Results In control group there was no significant difference in the nonlinear indexes of EEG between C3 and CA at all time points. In infarction group there was no significant difference in the EEG nonlinear indexes between C3 and CA before infarction but the values of the 3 nonlinear indexes of EEG were significantly lower at CA than at C3 starting from 5 min after infarction and lower at CA at 30 min and 60 min after infarction than the baseline value before infarction. Conclusion The D2 , ApEn and Cx values recorded at isehemic region were significantly decreased after infarction and can be used for focal cerebral iscbemia monitoring.