Cohen N, Lubart R, Rubinstein S, Breitbart H
Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
Photochem Photobiol. 1998 Sep;68(3):407-13.
Irradiation of mouse spermatozoa by 630 nm He-Ne laser was found to enhance the intracellular calcium levels and fertilizing potential of these cells. The effect of light on calcium transport and on fertilization rate was abrogated in the absence of Ca2+ during the irradiation time, indicating that the effect of light is Ca2+ dependent. The stimulatory effect of light on Ca2+ uptake was abolished in the presence of a voltage-dependent Ca(2+)-channel inhibitor nifedipine, indicating the involvement of a plasma membrane voltage-dependent Ca2+ channel. Furthermore, the stimulatory effect of light was completely inhibited by the mitochondrial uncoupler FCCP, indicating that laser irradiation might affect the mitochondrial Ca2+ transport mechanisms. A causal association between laser irradiation, reactive oxygen species (ROS) generation and sperm function was indicated by studies with ROS scavengers, superoxide dismutase (SOD) and catalase, and exogenous hydrogen peroxide. The SOD treatment, which enhanced H2O2 production, resulted in increased Ca2+ uptake and enhanced fertilization rate. On the other hand, catalase, which decomposes H2O2, impaired the light-induced stimulation in Ca2+ uptake and the fertilization rate. Taken together, the data suggest that H2O2 might be involved in the irradiation effects, and indeed laser irradiation enhances the production of H2O2 by spermatozoa. These results indicate that the effect of 630 nm He-Ne laser irradiation is mediated through the generation of H2O2 by the spermatozoa and that this effect plays a significant role in the augmentation of the sperm cells' capability to fertilize metaphase II-arrested eggs in vitro.
研究发现，用630纳米氦氖激光照射小鼠精子可提高这些细胞的细胞内钙水平和受精潜力。在照射期间缺乏Ca2+的情况下，光对钙转运和受精率的影响消失，这表明光的作用依赖于Ca2+。在存在电压依赖性Ca(2+)通道抑制剂硝苯地平的情况下，光对Ca2+摄取的刺激作用被消除，这表明质膜电压依赖性Ca2+通道参与其中。此外，线粒体解偶联剂FCCP完全抑制了光的刺激作用，这表明激光照射可能影响线粒体Ca2+转运机制。用活性氧清除剂、超氧化物歧化酶(SOD)和过氧化氢酶以及外源性过氧化氢进行的研究表明，激光照射、活性氧(ROS)生成与精子功能之间存在因果关系。增强H2O2生成的SOD处理导致Ca2+摄取增加和受精率提高。另一方面，分解H2O2的过氧化氢酶削弱了光诱导的Ca2+摄取刺激和受精率。综上所述，数据表明H2O2可能参与了照射效应，实际上激光照射增强了精子产生H2O2的能力。这些结果表明，630纳米氦氖激光照射的效应是通过精子产生H2O2介导的，并且这种效应在增强精子细胞体外使中期II期阻滞的卵子受精的能力方面起着重要作用。
