醋酸棉酚对大鼠体内及离体生精细胞蛋白质及核酸合成影响的观察

OBSERVATIONS OF THE GOSSYPOL EFFECTS ON THE PROTEIN AND NUCLEIC ACID SYTHESIS IN SPERMATOGENIC CELLS OF RAT TESTIS IN VIVO AND IN VITRO

为了分析棉酚抗生育的作用机理,本实验对大鼠睾丸生精细胞进行了体内和离体的氨基酸并合实验研究。大鼠按每日30毫克/公斤体重的棉酚剂量,连续灌服3,4,6,6周后取材。取材前2小时分别作睾内注射^(3)H-精氨酸,^(3)H-赖氨酸和^(3)H-5-尿嘧啶核苷,按常规取出睾丸制成放射自显片进行观察。离体实验则将上述睾丸中分离的生精细胞与同位素标记的氨基酸分别温育后,测定其并合的放射活性。实验结果表明棉酚对生精细胞并合^(3)H-赖氨酸和^(3)H-5-尿嘧啶核苷的能力没有明显影响。但对变态后期(11~19期)精子细胞并合^(3)H-精氨酸的活动则有明显的干扰作用,标记率明显下降。本实验结果表明进行选择性并合精氨酸替代赖氨酸合成组蛋白阶段的变态后期精子细胞对棉酚较为敏感。对该转换阶段受到干扰与精子丧失受精能力导致不育的可能性进行了讨论。

In order to analyse the mechanism of Gossypol antifertility action,studies in vivo and in vitro on the incorporation of tritium labeled amino acids and uridine in the spermatogenic cells of rat testes were carried out.Healthy adult male rats were selected for this experiment.Each animal received a daily dose of 30mg/kg of Gossypol for 3,4,5 and 6 weeks consecutively.Testes were recovered two hours after intratesticular injection of^(3)H-arginine,^(3)H-lysine or^(3)H-5-uridine respectively,and processed for autoradiographic observations.Quantitative determination of radioactivity of isolated spermatids and spermatocytes which had been incubated in vitro in media containing the above isotopes were also made,and comparison was made between the Gossypol treated cells and that of controls.The results demonstrated that there were no observable inhibitive effect of Gossypol on the incorporation of^(3)H-lysine and^(3)H-uridine in spermatogenic cells either in vivo or in vitro experiments,while the activity as well as frequency of labeling of^(3)H-arginine in spermatids of 11~19 stages were shown to be obviously decreased.This date indicated that the spermatids of late stages which incorporated^(3)H-arginine selctively for the synthesis of arginine-rich histone were the most sensitive in response to Gossypol.The possible relationship between the interference with the synthesis of argininerich histone and the loss of fertilizing capacity of spermatozoa was discussed.