选择性5α-还原酶抑制剂与十一酸睾酮合用对雄性大鼠生殖功能的影响

目的: 观察 5α 还原酶抑制剂与十一酸睾酮合用对雄性大鼠的生殖功能影响,从而探讨双氢睾酮是否参与生精及精子成熟的激素调节过程。　方法: 设立对照组后,给雄性大鼠经食道喂饲选择性 5α 还原酶抑制剂非那甾胺,并肌肉注射十一酸睾酮。观察大鼠生殖腺重量与组织学变化,血清睾酮、双氢睾酮水平,附睾精子计数和配对雌性大鼠妊娠胎仔数等变化情况。　结果: 与正常对照组相比,①非那甾胺减轻雄性大鼠的前列腺、睾丸和附睾的重量。合用外源性长效睾酮可以拮抗非那甾胺对大鼠前列腺重量的抑制作用。②非那甾胺使大鼠血清睾酮水平上升,而双氢睾酮显著下降。加用十一酸睾酮后的FT组血清睾酮和双氢睾酮水平均明显高于F组。③较大剂量的非那甾胺对大鼠的附睾精子计数,精子活率均有抑制作用,而且使精子畸形率明显升高和配对雌鼠的妊娠胎仔数减少。④非那甾胺与十一酸睾酮合用对大鼠的附睾精子计数与活率的抑制作用并没有得到进一步加强,虽然精子畸形率进一步升高,但配对雌鼠的妊娠胎仔数比T组却显著增加。　结论: 5α 还原酶抑制剂非那甾胺可以通过减少双氢睾酮的生成对大鼠的生殖器官和功能产生抑制作用。非那甾胺加用大剂量外源性雄激素并没有出现更强的抑制效应,反而部分抵消外源性雄激素的抑制生殖效应。

Effect of Selective 5α-Reductase Inhibitor or/and Testosterone Undecanoate on the Reproductive Function of Male Rats

OBJECTIVE: To investigate whether 5alpha-reductase inhibitor and dihydrotestosterone (DHT) play a role in spermatogenesis in male rats. METHODS: Thirty-two male rats were divided into 4 groups (Groups C, T, F and FT). Group C received plant oil injection and oral starch perfusion, Group T testosterone undecanoate (TU, 20 mg/kg) injection and oral starch perfusion, Group F plant oil injection and oral Finasteride perfusion, and Group FT TU (20 mg/kg) injection and oral Finasteride perfusion. Data on serum T and DHT, sperm count, sperm mobility and reproductive function were collected and analysed. RESULTS: (1) 5alpha-reductase inhibitor, Finasteride and TU reduced the weight of the testis and epididymis in the experiment groups compared with the negative control (Group C), but TU increased the weight of the prostate while Finasteride decreased it compared with the positive control (Group T). TU combined with Finasteride could counteract the effect of the weight increase of the prostate, but not that of the testis. (2) Finasteride, or Finasteride combined with TU, reduced the DHT but increased the testosterone level in comparison with the control group. (3) Both Finasteride and TU could inhibit epididymal sperm count and reproductive function compared with the control, but the effect was less significant in Group FT than in Group F. CONCLUSION: High dosages of 5alpha-reductase inhibitor, Finasteride, can suppress male reproductive function, but the inhibiting effect could be counteracted by administration of 5alpha-reductase inhibitor along with TU.