低频脉冲电磁场对大鼠应激性溃疡胃壁血液循环及超微结构的影响

Effects of low frequency pulsed electromagnetic field on stomach blood circulation and ultra microstructure of stress ulcer in rats

目的:探讨低频脉冲电磁场非热生物效应对大鼠应激性溃疡胃壁血液循环及其组织超微结构恢复的影响。方法:将36只SD大鼠随机等分为空白对照组、溃疡无干涉组、溃疡照射组3组。在低压低氧环境下,采用水浸束缚的方法构造大鼠应激性溃疡动物模型。首先,以单片机为基础,研制频率、幅值和占空比独立可调的低频脉冲电磁场发生装置,然后采用该装置对溃疡照射治疗组大鼠胃部区域进行照射,每天照射3 h。在造模后1、3、5、7 d,通过血清NO浓度测定及超声微泡造影方法观测胃壁血液循环的变化;溃疡组织切片染色后,通过电子显微镜观察胃壁组织超微结构病理学改变。结果:在不同的时间点,溃疡照射组大鼠血清NO浓度和微泡浓度明显高于溃疡无干涉组(P<0.05),且病理学观察表明溃疡照射组胃壁组织损伤修复明显较溃疡无干涉组快(P<0.05)。结论:一定参数的低频脉冲电磁场能够改善溃疡血液循环情况和加速组织的恢复。

Objective To determine non-thermal biological effect of low frequency pulsed electromagnetic field （LFPEF）on the stomach blood circulation and ultra microstructure of rat stress ulcer. Methods Thirty-six Sprague-Dawley rats were assigned to three equal groups：control,ulcer without interference group（UW）and ulcer exposure groups（UE）.The rats stress ulcer models were constructed with the combination method of soak and bind in the low-pressure and hypoxia circumstance. Based on the singlechip,a LFPEF generator with adjustable frequency, amplitude and duty ratio was developed. Then the stomachs of the rats were exposed to the LFPEF generator 3 hours per day.On days 1,3,5 and 7,the blood circulation of the stomach was analyzed by the content of the serum NO and contrast ultrasonography.In addition,the ulcer tissue was taken out for section-staining. Finally, the pathological change of the stomach ultra microstructure was observed under a light microscope. Results On different days, the contents of the serum NO and microbubble concentration of UE group were significantly higher than those of the UW group（P〈0.05）. The pathological observation showed that the restoration of the gastric tissue in UE group was faster than that in the UW group（P〈0.05）.Conclusion LFPEF with certain proper parameter could improve the gastric tissue blood circulation and accelerate the stress ulcer restoration.