棉酚对大鼠血睾屏障的影响

用30mg/kg体重的醋酸棉酚喂大白鼠,从服药的第3周,即发现曲细精管的电位差由34℃时的对照值4.75±1.39mV降为 3.63±0.79mV,并且失去了电位差-温度之间的线性关系.服药至第5周时,硝酸镧可透入基底膜,进入上皮内和部分支持细胞紧密连接结构;服药8周后,硝酸镧可透过支持细胞的紧密连接结构,同时该区排列变为不规则.提示棉酚可导致血睾屏障功能障碍,从而破坏精子发育环境,这可能是棉酚抑制精子生成的主要原因之一。     

棉酚对大鼠抗精子发生作用的细胞学、放射自显影及超微结构的观察

本文报道棉酚干扰大鼠睾丸精子发生过程及其作用部位的细胞学、放射自显影和超微结构的观察结果。睾丸生精上皮在眼药2—3周后开始出现细胞损伤;4周后精子细胞和中、晚期精母细胞大部退化消失,严重损伤的曲细精管萎缩变形,只残存以支持细胞和精原细胞为主的网状结构,间质细胞和附睾管未见有形态损伤,附属性腺亦无改变。细胞学和并合~(14)C-赖氨酸、亮氨酸和精氨酸的放射自显片观察均证明精子细胞和精母细胞出现损伤的时间最早,破坏程度最严重,是对棉酚最敏感的生精细胞,电子显微镜下亦可见这两类细胞出现明显的超微结构改变,其中变态晚期精子细胞的线粒体损伤最为明显,精原细胞仍保持并合~3H-胸腺嘧啶核苷的能力,表明不同生精细胞对棉酚有不同的敏感性。根据上述结果,文中对棉酚抗精子发生的作用部位、途径及其意义进行了分析和讨论。     

EFFECT OF GOSSYPOL ON THE POTENTIAL DIFFERENCE OF RAT SEMINIFEROUS TUBULES

The p.d. of the rat seminiferous tubules was 4.75±1.39 mV (lumen negative) at 35℃ and varied linearly with temperatures from 26 to 40℃.A depolarization of the seminiferous tubules was found in the rats administered with gossypol at the dosage of 30 mg/kg body weight for 3 weeks, the p.d. lowered to 3.63±0.79 mV at 35℃ and was independent of the changes of seminiferous tubules temperature. In the 5-week-gossypol-treatment group, the tracer penetrated not only the myoid cell layer, but also went beyond the tight junction complexes between Sertoli cells. The lanthanum appeared in the cleft surrounding spermatogonia. In the 8-week-gossypol-treatment group, the lanthanum was found in the adluminal compartment.It indicates that gossypol can cause a dysfunction of the Sertoli cells and blood-testis barrier and disturb a good physiological environment for the developing spermatecytes.