目的 观察T3干预对氟他胺(Flu)诱导的SD大鼠成年后生殖能力改善情况.方法 16只SD新生鼠随机分为2组:①正常组8只:正常孕鼠常规喂养;②T3(1d)组8只:正常孕鼠常规喂养,出生后第1天(PD1)给予T315μg/(kg·d)至PD13d.70只Flu诱导新生鼠随机分为2组:①Flu组35只:常规喂养;②Flu+T3(1d)组35只:PD1d给予T315μg/(kg·d)至PD13d.观察干预后各组小鼠隐睾发生率、睾丸、附睾、精子计数、组织学改变等.结果 Flu组隐睾发生率为45%(9/20),Flu+T3(1d)组隐睾发生率为25%(4/16),差异无统计学意义(P>0.05).Flu及Flu+T3(1d)干预组隐睾雄鼠的附睾中均无精子;两组中所有的下降睾丸(包括单侧隐睾健侧)的附睾精子计数中,均存在无精子和少精子情况,两组差异无统计学意义(P>0.05).T3(1d)组、Flu诱导正常有精子附睾的精子计数与正常对照组比较差异有统计学意义(P<0.05),而Flu+T3(1d)组与正常对照组比较差异无统计学意义(P>0.05).正常组及T3(1d)组雄鼠均可使正常雌鼠受孕,Flu组及Flu+T3(1d)组雄鼠,因均合并有尿道下裂,未能使雌鼠受孕.在有精子睾丸中,T3(1d)组睾丸质量、体积、脏器系数与正常组比较差异无统计学意义(P>0.05);Flu+T3(1d)组睾丸质量、体积脏器系数均小于Flu组,差异有统计学意义(P<0.05);Flu组与正常组差异无统计学意义(P>0.05).生精上皮计数及Johnson评分显示:正常对照组均高于T3(1d)组,Flu+T3(1d)有精子组低于Flu有精子组,Flu无精子组高于Flu+T3(1d)组,差异有统计学意义(P<0.01),但Flu诱导隐睾与Flu+T3(1d)隐睾组比较差异无统计学意义(P>0.05).结论 T315μg/(kg·d)剂量强度合理,T3可以降低Flu诱导暴露后隐睾发生率;对Flu诱导后的雄性仔鼠的生精功能有一定的改善作用,但并不能促进睾丸发育,提高精子生成率,不能显著改善生殖功能.%Objective To observe the effect of T3 intervention on the reproductive capacity improvement of flutamide ( Flu) induced adult rats. Methods 16 SD rats were randomly divided into normal group ( n=8 ) and T3 group ( n=8 ) . All the pregnant rats were conventionally fed. And the neonatal rats in the T3 group received T3 on a dosage of 15μg/( kg·d) from 1 day after birth(PD1d)to 13 days after birth(PD13d). 70 Flu-induced neonatal rats were randomly divided into Flu group(n=35)and Flu+T3(1d)group(n=35). The neonatal rats in the Flu group were conventionally fed. And the rats in the Flu+T3(1d)group were given T3 on a dosage of 15μg/(kg·d)from PD1d to PD13d. The incidence rate of cryptorchidism,testis,epididymis,sperm count and histological changes were observed. Result The incidence rate of cryptorchidism was 45%(9/20)in the Flu group and 25%(4/16)in the Flu + T3(1d)group,with no significant difference(P>0. 05). There were no spermatozoa in the epididymis of male rats with cryptorchidism in the Flu and Flu + T3(1d)group. And aspermia and oligospermia were observed in the epididymis of all descending testes(including normal testes in unilateral cryptorchidism)in both Flu and Flu + T3(1d)group. And the differ-ence was not statistically significant(P >0.05). The numbers of spermatozoa in the T3(1d)group and in normal testes in the Flu-induced group were significantly different from that of the normal control group ( P<0. 05 ) . While between Flu + T3 group and normal control group,the difference did not demonstrate statistical significance(P>0. 05). Male rats in normal group and T3 (1d)group can impregnate normal female rats,but male rats in the Flu group and Flu + T3(1d)group failed to impregnate normal female rats because of congenital hypospadias. For testes with spermatozoa,the differences in mass,volume,organ coefficient of tes-tis between T3(1d)group and normal control group did not demonstrate statistical significance(P>0. 05). While mass,volume,or-gan coefficient of testis in the Flu + T3(1d)were significantly less than those in the normal control group(P<0. 05). The differ-ence in those indexes between Flu group and normal group also did not demonstrate significance ( P>0. 05 ) . And the number of spermatogenic epithelium and the Johnson score in the normal,Flu + T3(1d)spermatozoa group and Flu aspermia group were re-spectively larger than those in the T3(1d)group,Flu spermatozoa group and Flu+T3(1d)aspermia group(P<0. 01). But when cryptorchidism was induced,the difference between the Flu group and Flu + T3(1d)group lost significance(P>0. 05). Conclu-sion The T3 dosage of 15μg/( kg·d) was reasonable. T3 might reduce the incidence rate of cryptorchidism after flu exposure and improve the spermatogenic function. But T3 did not seem to promote the development of testis,improve sperm production rate and reproductive function.
展开▼
