Amory John K, Wang Christina, Swerdloff Ronald S, Anawalt Bradley D, Matsumoto Alvin M, Bremner William J, Walker Susan E, Haberer Lynda J, Clark Richard V
Department of Medicine, Veterans Affairs-Puget Sound Health Care System, University of Washington, Seattle, WA 98195, USA.
J Clin Endocrinol Metab. 2007 May;92(5):1659-65. doi: 10.1210/jc.2006-2203. Epub 2007 Feb 13.
Dutasteride and finasteride are 5alpha-reductase inhibitors (5ARIs) that dramatically reduce serum levels of dihydrotestosterone (DHT).
Because androgens are essential for fertility, we sought to determine the impact of 5ARI administration on serum testosterone (T), DHT, and spermatogenesis. DESIGN, SETTING, SUBJECTS, AND INTERVENTION: We conducted a randomized, double-blinded, placebo-controlled trial in 99 healthy men randomly assigned to receive dutasteride (D; 0.5 mg) (n = 33), finasteride (F; 5 mg) (n = 34), or placebo (n = 32) once daily for 1 yr.
Blood and semen samples were collected at baseline and 26 and 52 wk of treatment and 24 wk after treatment and were assessed for T, DHT, and semen parameters.
D and F significantly (P < 0.001) suppressed serum DHT, compared with placebo (D, 94%; F, 73%) and transiently increased serum T. In both treatment groups, total sperm count, compared with baseline, was significantly decreased at 26 wk (D, -28.6%; F, -34.3%) but not at 52 wk (D, -24.9%; F, -16.2%) or the 24-wk follow-up (D, -23.3%; F, -6.2%). At 52 wk, semen volume was decreased (D, -29.7%; F, -14.5%, significantly for D) as was sperm concentration (D, -3.2%; [corrected] F, -7.4%, neither significant). There was a significant reduction of -6 to 12% in sperm motility during treatment with both D and F and at follow-up. Neither treatment had any effect on sperm morphology.
This study demonstrates that the decrease in DHT induced by 5ARIs is associated with mild decreases in semen parameters that appear reversible after discontinuation.
度他雄胺和非那雄胺是5α-还原酶抑制剂（5ARIs），可显著降低血清双氢睾酮（DHT）水平。
由于雄激素对生育至关重要，我们试图确定服用5ARI对血清睾酮（T）、DHT和精子发生的影响。设计、地点、研究对象和干预措施：我们对99名健康男性进行了一项随机、双盲、安慰剂对照试验，这些男性被随机分配为每天服用度他雄胺（D；0.5mg）（n = 33）、非那雄胺（F；5mg）（n = 34）或安慰剂（n = 32），持续1年。
在基线、治疗26周和52周以及治疗后24周采集血液和精液样本，并评估T、DHT和精液参数。
与安慰剂相比，D和F显著（P < 0.001）抑制血清DHT（D为94%；F为73%），并使血清T短暂升高。在两个治疗组中，与基线相比，总精子计数在26周时显著下降（D为-28.6%；F为-34.3%），但在52周时（D为-24.9%；F为-16.2%）或24周随访时（D为-23.3%；F为-6.2%）未下降。在52周时，精液量减少（D为-29.7%；F为-14.5%，D组显著），精子浓度也减少（D为-3.2%；[校正后]F为-7.4%，均无显著差异）。在D和F治疗期间及随访时，精子活力显著降低6%至12%。两种治疗对精子形态均无影响。
本研究表明，5ARIs诱导的DHT降低与精液参数轻度降低有关，停药后这些降低似乎是可逆的。
