Mrsny R, Griffith O H
J Reprod Fertil. 1985 May;74(1):127-34. doi: 10.1530/jrf.0.0740127.
Photoelectron images of mammalian spermatozoa were obtained by subjecting the specimens to u.v.-irradiation and focussing the emitted electrons by electron optics (photoelectron microscopy). Guinea-pig, hamster and human spermatozoa were fixed in glutaraldehyde, deposited on conductive glass discs, and dehydrated. Sufficient quantities of photoelectrons were released from the surface of spermatozoa to produce images without staining, coating or metal shadowing. The large planar heads of guinea-pig spermatozoa were easily resolved with good delineation of acrosomal and postacrosomal regions. Residual vesicles could be visualized on the surface of the inner acrosomal membrane of spermatozoa that had undergone the acrosome reaction. Also detectable in these photoelectron images were finer membrane surface details, periodicities in the midpiece region of the tail which coincided with the distribution of mitochondria, and periodicities in the principal piece which appeared to be related to fibrous sheath components. Hamster spermatozoa were similarly well resolved but human spermatozoa were more difficult to image because of their increased surface curvature. The mechanism responsible for detection of these surface details is primarily topographical contrast rather than material contrast, since spermatozoa coated with a thin layer of gold or platinum exhibited similar features, although at reduced resolution, as the uncoated specimens.
通过对标本进行紫外线照射并用电子光学方法聚焦发射出的电子（光电子显微镜），获得了哺乳动物精子的光电子图像。豚鼠、仓鼠和人类精子用戊二醛固定，沉积在导电玻璃圆盘上，然后脱水。精子表面释放出足够数量的光电子，从而无需染色、镀膜或金属投影就能产生图像。豚鼠精子的大扁平头部很容易分辨，顶体和顶体后区域轮廓清晰。在经历了顶体反应的精子顶体内膜表面可以看到残留小泡。在这些光电子图像中还能检测到更细微的膜表面细节、尾部中段与线粒体分布一致的周期性结构，以及主段似乎与纤维鞘成分相关的周期性结构。仓鼠精子同样分辨得很好，但人类精子由于表面曲率增加，更难成像。检测这些表面细节的机制主要是地形对比度而非物质对比度，因为涂有一层薄金或铂的精子与未涂层的标本表现出相似的特征，尽管分辨率较低。
