低频超声治疗对SD大鼠颊囊黏膜溃疡愈合的影响

Effect of low-frequency ultrasound therapy on oral mucosal ulcer healing in SD rats

目的探讨低频超声对大鼠实验性口腔黏膜溃疡愈合时间及溃疡组织中一氧化氮(NO)和一氧化氮合酶(NOS)含量的影响。方法健康Sprague-Dawley(SD)大鼠36只,雌雄各半,完全随机分为6组(n=6),1组设为正常对照组,其余5组利用氧自由基诱导法+物理烧伤法建立SD大鼠颊囊黏膜口腔溃疡动物模型,分别为溃疡组、药物组和低频超声组(1.1、1.58、2.06 W)。末次治疗24 h后观察溃疡愈合时间,并采用分光光度计测定大鼠口腔颊囊黏膜组织中NO、NOS含量。结果大鼠溃疡病理特点与人类口腔溃疡病理特点基本相似。低频超声组较溃疡组及药物组的溃疡愈合时间短。NO活性测定结果显示,低频超声组1.1、1.58、2.06 W[分别为(9.86±1.69)、(9.42±1.34)、(8.51±1.26)μmol/g]较溃疡组[(23.85±4.81)μmol/g]显著降低(P<0.05),与正常对照组(10.88±1.68)μmol/g比较无统计学差异(P>0.05);NOS活性检测结果同样表明,低频超声组1.1、1.58、2.06 W[分别为(3.89±0.72)、(4.35±0.53)、(4.74±0.81)μmol/g]较溃疡组[(6.48±0.77)μmol/g]显著降低(P<0.05),与正常对照组(3.83±0.99)μmol/g比较无统计学差异(P>0.05)。结论适合剂量参数的脉冲低频超声能有效降低溃疡组织中的NO、NOS活性含量,对溃疡的愈合有一定的促进作用。

Objective To observe the effect of low-frequency ultrasound therapy on healing time and the contents of NO and NO synthetase（NOS） in ulcer tissues of rat models with oral mucosal ulcer.Methods Thirty-six Sprague-Dawley（SD） rats were randomly divided into six groups,including a normal control group,a model group,a 1% iodine glycerin group and three low-frequency ultrasound groups（with different energy levels of 1.1 W,1.58 W and 2.06 W,respectively）.Except for the normal control group,the rats of the other five groups were given oxygen free radicals and physical burn to construct the oral mucosal ulcer models.At 24 h after last treatment,three rats of each group were sacrificed and the cheek pouches were obtained for the detection of NO and NOS contents in the mucosal tissues by spectrophotometry.The ulcer healing was also observed for 8 consecutive days.The efficiency of low-frequency ultrasound therapy with different energy levels was evaluated.Results The healing time of the low-frequency ultrasound groups was shorter than that of the model group and 1% iodine glycerin group.The contents of NO and NOS in the low-frequency ultrasound groups（NO： 9.86±1.69,9.42±1.34 and 8.51±1.26 μmol/g;NOS： 3.89±0.72,4.35±0.53 and 4.74±0.81 μmol/g） were significantly lower than those in the model group（NO： 23.85±4.81 μmol/g;NOS： 6.48±0.77 μmol/g）（P〈0.05）,but were not significantly different from those in the normal control group（NO： 10.88±1.68 μmol/g;NOS： 3.83±0.99 μmol/g,P〈0.05）.Conclusion Low-frequency ultrasound therapy with appropriate energy levels can effectively reduce the contents of NO and NOS in ulcer tissues,and can promote the process of ulcer healing.