不同浓度艾烟对大鼠肺组织及血清中CD4^+/CD8^+影响

Effects of different concentrations of moxa smoke on lung tissue and CD4^+/CD8^+ T cell ratio in rats

目的了解吸入不同浓度艾烟对大鼠肺组织结构及血清中CD4^+/CD8^+的影响,探讨艾烟所导致的肺组织形态改变及免疫调节作用与其浓度的关系,为临床安全使用艾灸疗法提供理论依据。方法清洁级2月龄雄性Wistar大鼠40只,随机分为正常对照组及低、中、高浓度艾烟暴露组4组,每组10只,分别暴露于无艾烟环境及10、25、70 g艾绒完全燃烧后的艾烟中,每天2 h,持续30 d;采用显微镜观察大鼠肺组织形态变化,应用流式细胞术检测大鼠外周血中CD4^+及CD8^+T淋巴细胞百分率,并计算CD4^+/CD8^+值。结果高浓度艾烟暴露组大鼠肺组织中出现炎症反应,低、中浓度艾烟暴露组大鼠肺组织无显著改变;高浓度艾烟暴露组大鼠CD8^+T淋巴细胞百分率为(37.13±2.23)%,均高于正常对照组及低、中浓度艾烟暴露组CD8^+T淋巴细胞百分率的(34.45±5.14)%、(33.84±3.23)%、(34.19±4.27)%(均P<0.05);高浓度艾烟暴露组CD4^+/CD8^+值为(1.46±0.29),均低于正常对照组及低、中浓度艾烟暴露组CD4^+/CD8^+值的(1.53±0.43)、(1.55±0.37)、(1.58±0.41)(均P<0.05)。结论不同浓度艾烟对大鼠的肺组织形态及免疫系统均有影响,其中低、中浓度的艾烟较高浓度的艾烟对肺脏损伤小,且能够更好地调节免疫水平,提高机体免疫功能。

Objective To explore dose-dependent effect of moxa smoke inhalation on lung tissue structure and blood CD4^+/CD8^+T cell ratio in rats and to provide a theoretical basis for moxibustion therapy safety in clinical practice.Methods Forty clean-grade 2-month-old male Wistar rats were randomly divided into 4 groups(10 in each group):a normal control(in moxa smoke-free environment)and low,moderate,and high moxa smoke group(exposed to smoke from fullburning of 10,25 and 70 grams moxa 2 hours a day continuously for 30 days).Microscopic examinations were performed to observe morphological changes in the rats′lung tissues.CD4^+and CD8^+T lymphocytes in peripheral blood of the rats were detected with flow cytometry.Results Obvious inflammatory reaction was observed only in lung tissues of the rats exposed to high moxa smoke.The percentage of CD8^+T lymphocytes in high moxa smoke exposure rats was 37.13^+2.23%,significantly higher than that in normal control rats(34.45^+5.14%),and in the rats with low(33.84^+3.23%)and moderate(34.19^+4.27%)moxa smoke exposure(P<0.05 for all).The CD4^+/CD8^+T cell ratio(1.46±0.29)in the rats with high moxa smoke exposure was significantly lower than that in normal control rats(1.53^+0.43)and in the rats with low(1.55^+0.37)and moderate moxa smoke exposure(1.58^+0.41)(all P<0.05).Conclusion Moxa smoke has dose-dependent effect on lung tissue morphology and immune system in rats.Low and moderate concentrations of moxa smoke induce no significant damage in lung tissues but can improve immune function in rats.