CAJ | 학술논문

目的：评价大气黑碳（black carbon，BC）与臭氧处理黑碳（ozonized black carbon，O3-BC）对机体的遗传毒性，并从氧化应激的角度探讨其机制。方法：将74只体重为（28．0±1．5） g的雄性ICR小鼠随机分为7组，即磷酸盐缓冲液对照组和两种颗粒物的50μg、100μg、200μg混悬液滴注组（每次每只动物分别滴注50、100、200μg）。最高剂量组（200μg组）为12只，其余组均为10只。染毒为每天气管滴注1次，连续滴注4天，末次染毒24 h后处死动物。测定血清过氧化氢酶（catalase，CAT）活性、肺匀浆丙二醛（malondialdehyde，MDA）含量、血清及随机尿8-羟基脱氧鸟苷（8-hydroxyguanosine ，8-OHdG）水平，对骨髓涂片进行微核计数及肺组织病理分析。结果：小鼠一般情况良好，与对照组相比染毒组肝脏器系数降低（P＜0．05）；100μg和200μg两种颗粒物组血清CAT活性较对照组增加（P＜0．05），微核率亦较对照组增加（P＜0．05）；各组血清及尿中8-OHdG和肺匀浆MDA差异无统计学意义；组织病理观察，暴露于颗粒物后肺组织出现炎症反应。结论：急性暴露于高剂量BC及O3-BC的小鼠体内氧化应激水平升高，并出现遗传损伤，但两种颗粒物毒性无明显差异， O3处理是否增加BC的遗传毒性还有待于进一步探讨。
목적：평개대기흑탄（black carbon，BC）여취양처리흑탄（ozonized black carbon，O3-BC）대궤체적유전독성，병종양화응격적각도탐토기궤제。방법：장74지체중위（28．0±1．5） g적웅성ICR소서수궤분위7조，즉린산염완충액대조조화량충과립물적50μg、100μg、200μg혼현액적주조（매차매지동물분별적주50、100、200μg）。최고제량조（200μg조）위12지，기여조균위10지。염독위매천기관적주1차，련속적주4천，말차염독24 h후처사동물。측정혈청과양화경매（catalase，CAT）활성、폐균장병이철（malondialdehyde，MDA）함량、혈청급수궤뇨8-간기탈양조감（8-hydroxyguanosine ，8-OHdG）수평，대골수도편진행미핵계수급폐조직병리분석。결과：소서일반정황량호，여대조조상비염독조간장기계수강저（P＜0．05）；100μg화200μg량충과립물조혈청CAT활성교대조조증가（P＜0．05），미핵솔역교대조조증가（P＜0．05）；각조혈청급뇨중8-OHdG화폐균장MDA차이무통계학의의；조직병리관찰，폭로우과립물후폐조직출현염증반응。결론：급성폭로우고제량BC급O3-BC적소서체내양화응격수평승고，병출현유전손상，단량충과립물독성무명현차이， O3처리시부증가BC적유전독성환유대우진일보탐토。
Objective:To make an assessment on the genotoxicity caused by black carbon ( BC ) and ozonized black carbon (O3-BC).Methods: In this study, 74 healthy male ICR mice [weighed (28 ± 1.5) g] were randomly divided into 7 groups, including one phosphate buffer solution ( PBS) control group and six particles exposed groups by intratracheal instillation with either BC or O 3-BC at the doses of 50, 100, 200 μg/mouse, respectively.There were 12 mice in the groups of 200μg/mouse and 10 mice in others.The mice were sacrificed 24 h after four intratrachealinstillations .The activities of catalase ( CAT) in serum and the levels of malondialdehyde ( MDA) in lung tissue homogenate were measured . As the DNA damage mark , 8-hydroxyguanosine ( 8-OHdG ) in urine and serum were quantified with ELISA method.Micronucleus test was used for potential genotoxicity of BC and O 3-BC.Hematoxylin and eosin staining was used to stain lung paraffin section .Results:The mice were in good condition during instillation , and the liver coefficient of the test groups was significantly lower than that of the control group (P<0.05).The activities of CAT in serum significantly increased in the 100 μg/mouse and 200μg/mouse groups after being exposed to these two kinds of particles .The micronucleus rate in allthe BC and O3-BC exposed groups increased ( P <0.05), but there was no statistically significant difference among the groups in the levels of 8-OHdG in serum and urine and MDA in lung tissue homogenate .In-flammatory response was found in the lung tissue under the microscope after exposure to BC and O 3-BC. Conclusion:Intratracheal instillation of BC and O 3-BC induced increasing of oxidative stress and genetic damage in mice .But there was no significant difference between these two particles in toxicity .Whether the genotoxicity of O 3-BC is higher than that of BC or not is uncertain .Further research is needed .