苯并(a)芘诱发小鼠实体瘤及其对机体IL-2、IL-6的影响

Solid tumors induced by benzo( a) pyrene in mice and its effects on IL-2 and IL-6

目的探索苯并(a)芘诱发小鼠实体瘤的情况及其对小鼠血清IL-2、IL-6的影响。方法 SPF级昆明种小鼠60只,雌雄各半,体重(20±2)g。随机分为三组:对照组、苯并(a)芘10 mg/kg组、苯并(a)芘20 mg/kg组(n=20),各组分别腹腔注射DMSO、10 mg/kg、20 mg/kg苯并(a)芘(注射体积0.1 ml/kg·bw),每日一次,连续10次。三个月后取血,ELISA测定血清IL-2及IL-6。取肝、肾、胃、肺,进行病理组织学检查。结果苯并(a)芘10 mg/kg组和20 mg/kg组,肝癌发生率为26.3%(5/19)和35.3%(6/17),胃癌发生率为0%(0/19)和41.2%(7/17);肾癌发生率为0%(0/19)和11.8%(2/17);癌前病变发生率,肝脏为73.7%(14/19)和64.7%(11/17),胃为68.4%(13/19)和29.4%(5/17),肾脏为47.4%(9/19)和58.8%(10/17)。实验各组癌前病变率均显著高于对照组(P<0.05);苯并(a)芘20 mg/kg组肝癌、胃癌、肾癌发生率均显著高于对照组(P<0.05);实验组肺脏未见明显损害。苯并(a)芘10 mg/kg组和20 mg/kg组血清IL-2、IL-6水平均显著低于对照组(P<0.01)。结论苯并(a)芘可诱发肝脏、胃、肾脏发生癌变或癌前病变,使小鼠血清IL-2、IL-6水平降低。

Objective To observe solid tumors induced by benzo（ a） pyrene in mice and to explore its effects on serum IL-2 and IL-6. Methods Sixty SPF Kunming mice,half male and half female,with the weight of（ 20 ± 2） g,were randomly divided into control group,benzo（ a） pyrene 10 mg / kg group and benzo（ a） pyrene 20 mg / kg group（ each n = 20）. The mice in the three groups were injected intraperitoneally with DMSO,10 mg / kg benzo（ a） pyrene and 20 mg / kg benzo（ a） pyrene in a volume of 0. 1 ml / kg. bw daily for 10 days. Blood was collected after three months and serum IL-2 and IL-6 were detected by ELISA. The liver,kidney,stomach and lung were subjected to histopathological examination. Results The cancer incidence rates in the livers,stomachs and kidneys of the mice in the benzo（ a） pyrene 10 mg / kg group and benzo（ a） pyrene 20 mg / kg group were 26. 3%（ 5 /19） and 35. 3%（ 6 /17）,0%（ 0 /19） and 41. 2%（ 7 /17）,0%（ 0 /19） and 11. 8%（ 2 /17）,respectively.The incidence rates of precancerous lesions in the livers,stomachs and kidneys of the mice in the benzo（ a） pyrene 10 mg / kg group and benzo（ a） pyrene 20 mg / kg group were 73. 7%（ 14 /19） and 64. 7%（ 11 /17）,68. 4%（ 13 /19） and 29. 4%（ 5 /17）,47. 4%（ 9 /19） and 58. 8%（ 10 /17）,respectively. The incidence rates of precancerous lesions were significantly higher in the benzo（ a） pyrene 10 mg / kg and 20 mg / kg groups than in the control group（ P〈0. 05）. The incidence rates of liver,stomach and kidney carcinomas were significantly higher in benzo（ a） pyrene 20 mg / kg group than in the control group（ P〈0. 05）. No obvious lesions were found in the lungs of the mice of the two experimental groups. Serum IL-2 and IL-6 levels were statistically lower in the benzo（ a） pyrene 10 mg / kg and 20 mg / kg groups than in the control group（ P〈0. 01）. Conclusions Benzo（ a） pyrene can induce cancers and precancerous lesions in the livers,stomachs and kidneys of the mice; moreover,it also can reduce the serum IL-2 and IL-6 levels.