Creech M M, Arnold E V, Boyle B, Muzinich M C, Montville C, Bohle D S, Atherton R W
Department of Zoology and Physiology, University of Wyoming, Laramie 82071, USA.
J Androl. 1998 Nov-Dec;19(6):667-74.
The effects of nitric oxide (NO) on sperm motility were examined in the fathead minnow, Pimephelas promelas, using computer-assisted sperm analysis (CASA). The observed effects underscore the dual nature of NO as both a low-concentration regulatory agent and, at higher doses, a cytotoxic agent. At 1 x 10(-6) M concentration, NO donor sodium nitroprusside (SNP) enhanced sperm motility percentages and increased CASA velocity parameters curvilinear velocity, straight-line velocity, and average path velocity, whereas 1 x 10(-2) M concentration inhibited percent motility and decreased velocities. Fathead minnow ova-produced NO was subsequently trapped as a paramagnetic ferrous iron complex and detected by electron spin resonance spectroscopy. The distinctive triplet spectrum, with a(N) = 12.5G and g(iso) = 2.04, was recorded during a critical 5-minute period following laying. Nitric oxide synthase (NOS) was histochemically localized at the micropyle of mature unfertilized fathead eggs, and an inhibitor of NOS blocked histochemical staining. CASA analysis of sperm motility in the presence of ovaproduced NO over an 8-minute time course reveals an optimum motility enhancement at 4 minutes that is similar to the effect of 1 x 10(-6) M SNP. This transient NO production by freshly laid ova and the localization of NOS near the site of sperm entry, together with the motility-enhancing effect of 1 x 10(-6) M SNP on sperm, indicates an active role for low-concentration NO in fertilization.
利用计算机辅助精子分析（CASA）技术，在黑头呆鱼（Pimephelas promelas）中研究了一氧化氮（NO）对精子活力的影响。观察到的结果强调了NO的双重性质，即低浓度时作为调节因子，而高剂量时则作为细胞毒性剂。在浓度为1×10⁻⁶ M时，NO供体硝普钠（SNP）提高了精子活力百分比，并增加了CASA速度参数，如曲线速度、直线速度和平均路径速度；而在浓度为1×10⁻² M时，则抑制了活力百分比并降低了速度。随后，黑头呆鱼卵产生的NO被捕获为顺磁性亚铁络合物，并通过电子自旋共振光谱法进行检测。在产卵后的关键5分钟内记录到了独特的三重态光谱，a(N)=12.5G，g(iso)=2.04。一氧化氮合酶（NOS）通过组织化学方法定位在成熟未受精卵的卵孔处，NOS抑制剂可阻断组织化学染色。在8分钟的时间进程中，对存在卵产生的NO时精子活力进行CASA分析，结果显示在4分钟时活力增强达到最佳，这与1×10⁻⁶ M SNP的作用效果相似。新产卵产生的这种短暂的NO生成以及NOS在精子进入部位附近的定位，再加上1×10⁻⁶ M SNP对精子的活力增强作用，表明低浓度NO在受精过程中发挥着积极作用。
