Effect of alpha-blockers on epididymal sperm concentration, motility and testicular productivity in the rat

Abstract

SDラットに塩酸ブナゾシンを短期投与群として1ヵ月, 長期投与群として3ヵ月, 体重当たり1mg/kg強制経口投与した.精子濃度は塩酸ブナゾシン投与で著明に増加したが, 運動性に差はみられなかった.精子の産生能もまた塩酸ブナゾシン投与で増加した.しかし, 短期投与群と長期投与群とでは精子濃度, 精子の産生能とも差は認められなかった.精巣上体尾部の精子濃度の増加した理由は, α遮断剤の投与で増加した精巣上体での精子の貯留スペース, 及び短くなった精子の精巣上体通過時間, によると考えられた.又, α遮断剤は精巣への影響もあると考えられた

The present study was undertaken to determine whether alpha-blockers affect epididymal sperm parameters and testicular spermatogenesis. Sprague-Dawley rats were given orally a 1 mg/kg body weight dose of Bunazosin, a selective alpha-adrenoreceptor antagonist, daily for one month as a short-term administration group and three months as a long-term administration group. Using a micropuncture technique, epididymal sperm concentration and sperm motility were measured. Epididymal sperm concentrations were significantly increased in the Bunazosin group, but progressive motility of spermatozoa were not altered. Daily testicular sperm production was also increased after administration of Bunazosin. There were no differences in epididymal sperm concentration and daily sperm production between the one-month group and three-month group. An epididymal wide storage capacity and short transit time after administration of the alpha-blocker could increase the sperm concentration in the cauda epididymidis. Because there were no differences in the epididymal sperm parameters and daily testicular sperm production between the two groups, these changes may occur at 1 month after administration of the alpha-blocker. Moreover, the alpha-blocker might affect testicular function.