摘要目的 探讨银杏叶片对砷暴露大鼠免疫毒性的干预作用,为砷中毒的预防和治疗提供实验依据.方法 40只Wistar大鼠,使用随机数字表法,按照体质量随机分为4组:对照组、染砷组、银杏叶片治疗组、自然恢复组,每组10只,对照组大鼠自由摄取正常普通饲料90d;其他组大鼠自由摄取含砷饲料90 d;自然恢复组大鼠自由摄取含砷(100 mg/kg)饲料90d后,再给予正常普通饲料饲养45 d;银杏叶片治疗组大鼠自由摄取含砷饲料90 d后,再给予银杏叶片溶液(25 mg/kg·bw)灌胃,6d/周,治疗45 d,治疗期间喂饲正常普通饲料.然后收集大鼠24 h尿液,测定大鼠尿砷含量,采集大鼠静脉血,检测T淋巴细胞亚群CD3+、CD4+、CD8+阳性率,血清抗体IgG、IgM、IgA及补体C3、C4含量.结果 染砷组、自然恢复组、银杏叶片治疗组大鼠尿砷几何均数(2.991、0.421、0.334 mg/g)均高于对照组[0.141 mg/g,P均＜0.05].自然恢复组、银杏叶片治疗组大鼠尿砷均低于染砷组(P均＜ 0.05),自然恢复组大鼠尿砷含量与银杏叶片治疗组比较,差异无统计学意义(P＞0.05).染砷组CD3+、CD4+细胞阳性率[(31.31±7.73)％、(25.94±12.49)％]、CD4+/CD8+比值(0.91±0.50)均低于对照组[(60.83±17.64)％、(42.11±12.92)％、1.80±0.88,P均＜0.05],血清中补体C4含量[(81.18±13.23) mg/L]高于对照组[(64.23±6.97) mg/L,P＜0.01];自然恢复组CD3+、CD4+细胞阳性率[(32.35±19.84)％、(28.00±16.10)％]、CD4+/CD8+比值(0.98±0.29)、血清IgG、IgA、IgM、C3、C4含量[(897.23±23.55)、(1032.72±0.35)、(443.65±1.02)、(557.33±39.86)、(76.92±17.99)mg/L]与染砷组[(31.31±7.73)％、(25.94±12.49)％,0.91±0.50,(917.02±15.96)、(1032.96±1.32)、(444.43±1.82)、(560.15±39.57)、(81.18±13.23)mg/L]比较差异均无统计学意义(P均＞ 0.05);银杏叶片治疗组CD3+、CD4+细胞阳性率[(54.00±19.31)％、(39.93±8.63)％]均高于染砷组[(31.31±7.73)％、(25.94±12.49)％,P均＜0.05],血清中补体C4含量[(66.99±5.66)mg/L]低于染砷组[(64.23±6.97) mg/L,P＜0.05];染砷组、自然恢复组、银杏叶片组CD8+细胞阳性率以及血清IgG、IgA、IgM、C3含量[(31.38±11.40)％,(917.02±1596)、(1 032.96±1.32)、(444.43±1.82)、(560.15±39.57)mg/L;(27.90±13.22)％,(897.23±23.55)、(1 032.72±0.35)、(443.65±1.02)、(557.33±39.86)mg/L; (28.21±8.42)％,(905.83±24.16)、(1 032.10±0.80)、(442.65±1.32)、(554.41±41.21)mg/L]与对照组[(27.22±13.00)％,(903.02±14.69)、(1 032.04±0.64)、(443.41±0.93)、(536.61±32.92)mg/L]比较差异均无统计学意义(P均＞ 0.05).结论 砷暴露可引起大鼠体内细胞免疫功能紊乱;停止砷暴露后,自然恢复效果欠佳;银杏叶片可提高砷中毒大鼠的免疫功能.

abstractsObjective To explore the effects of Gingko biloba on immune function of rats exposed to arsenic,and to provide experimental evidence for prevention and treatment of arsenic poisoning.Methods By using a random number table,40 Wistar rats were randomly divided into four groups according to body weight,10 rats in each group,including the control,arsenic exposure,Ginkgo biloba treatment and natural recovery groups.The control group rats with normal diet ad libitum 90 d; other groups were freely given feed containing arsenic,90 d; the natural recovery group rats were freely given arsenic (100 mg/kg) feed 90 d,and then given a normal diet for 45 d; Ginkgo biloba treatment rats ingested arsenic feed 90 d,and then give Ginkgo biloba solution(25 mg/kg·bw) orally,6 d/week,treatment 45 d,fed normal normal diet during treatment.24 h urine of rats were collected to measure the content of arsenic in urine.The blood of rats in heart were collected,to determine the positive rates of CD3+,CD4+,CD8+ cells and antibodies (IgG,IgM,IgA),complements (C3,C4).Results Urinary arsenic levels of rats in arsenic exposure,natural recovery,Ginkgo biloba treatment groups (2.991,0.421,0.334 mg/g) were higher than that of control group (0.141 mg/g,P ＜ 0.05).The content of urine arsenic of rats in natural recovery and Ginkgo biloba treatment groups were lower than that of arsenic exposure group (P ＜ 0.05).The content of urine arsenic of rats in natural recovery group was not different from that of Ginkgo biloba treatment group (P ＞ 0.05).The positive rates of CD3+,CD4+ [(31.31 ± 7.73)％,(25.94 ± 12.49)％] and CD4+/CD8+ ratio (0.91 ± 0.50) of arsenic exposure group in peripheral blood were lower than those of the control group [(60.83 ± 17.64)％,(42.11 ± 12.92)％,1.80 ± 0.88,all P ＜ 0.05],but complement C4 level [(81.18 ± 13.23) mg/L] in serum was significantly higher than that of the control group [(64.23 ± 6.97) mg/L,P＜ 0.01); the positive rates of CD3+,CD4+ [(32.35 ± 19.84)％,(28.00 ± 16.10)％],the ratio of CD4+/CD8+ (0.98 ± 0.29) of natural recovery group in peripheral blood and IgG,IgA,IgM,C3,C4 levels [(897.23 ± 23.55),(1 032.72 ± 0.35),(443.65 ± 1.02),(557.33 ± 39.86),(76.92 ± 17.99) mg/L] of natural recovery group in serum were not significantly different from those of arsenic exposure group [(31.31 ± 7.73)％,(25.94 ± 12.49)％,0.91 ± 0.50,(917.02 ± 15.96),(1032.96 ± 1.32),(444.43 ± 1.82),(560.15 ± 39.57),(81.18 ± 13.23)mg/L,all P ＞ 0.05); the positive rates of CD3+,CD4+ cells [(54.00 ± 19.31)％,(39.93 ± 8.63)％] of Ginkgo biloba treatment group were significantly higher than those of the arsenic exposure group [(31.31 ± 7.73)％,(25.94 ± 12.49)％,all P ＜ 0.05]; complement C4 level [(66.99 ± 5.66)mg/L] in serum was lower than that of the arsenism group [(64.23 ± 6.97) mg/L,P ＜ 0.01]; the positive rates of CD8+ in peripheral blood and IgG,IgA,IgM,C3 levels in serum of arsenic exposure group,natural recovery group,ginkgo biloba treatment group [(31.38 ± 11.40)％,(917.02 ± 15.96),(1 032.96 ± 1.32),(444.43 ± 1.82),(560.15 ± 39.57) mg/L; (27.90 ± 13.22)％,(897.23 ± 23.55),(1 032.72 ± 0.35),(443.65 ± 1.02),(557.33 ± 39.86)mg/L; (28.21 ± 8.42)％,(905.83 ± 24.16),(1 032.10 ± 0.80),(442.65 ± 1.32),(554.41 ± 41.21)mg/L] were not significantly different from those of the control group [(27.22 ± 13.00)％,(903.02 ± 14.69),(1 032.04 ± 0.64),(443.41 ± 0.93),(536.61 ± 32.92) mg/L,all P ＞ 0.05].Conclusions Arsenic can cause immune dysfunction in vivo in rat; even after ceased exposure to arsenic,the natural recovery is not good; Ginkgo biloba can enhance the immune function in arsenic poisoning rats.