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The Sperm-Class Analyser was validated for assessing morphometric parameters of the head and midpiece of unwashed and washed human ejaculated spermatozoa from volunteers providing a wide range of semen quality. A higher proportion of sperm could be assessed (86% fresh semen and 75% washed sperm) if Hemacolor staining was used rather than DiffQuik (80 and 73%) or Papanicolaou (78 and 68%). Different stains employed different fixatives and the area, length, width and perimeter of the sperm head was significantly larger for washed sperm stained by Hemacolor and DiffQuik. Acrosomal area ranged from 48 to 51% of the sperm head area and this percentage was larger for washed sperm stained with DiffQuik. Sperm at the end of the slide, distant from the initial semen droplet, were larger in area and perimeter than those at that site or in the middle. The high precision and reproducibility of the equipment required assessing only 50 sperm on the slide. Far greater variation was found in head width, relative acrosomal area and midpiece width between different slides prepared from the same ejaculate, highlighting the inherent variability within the ejaculate and smear preparation, and requiring more than one slide to be assessed.

Automated sperm morphology analysis (ASMA) technology has improved the assessment of sperm morphology, but the results depend on the use of adequate and standardized procedures. In this study the Sperm-Class AnalyzerÒ (SCA) ASMA system was used to assess sperm head morphometry in the Cynomolgus monkey and to evaluate the in¯uence of sample size, intraslide variation, and the use of three staining techniques on the accuracy of image processing and sperm head morphometry. Haematoxylin is the staining technique of choice for Cynomolgus spermatozoa, as optimum contrast of sperm heads with the surrounding background allows ef®cient segmentation, i.e. sperm head boundary detection, making the image analysis process more accurate. The analysis of 100 spermatozoa is recommended since a larger sample size did not result in more accurate sperm head morphometry. There were no differences in either the percentage of correctly binarized sperm heads or sperm head dimensions among samples obtained from different zones of the slides, although differences in stain intensity (grey level) were detected. The measurements made on Haematoxylin, Diff-Quik and Hemacolor-stained slides yielded different values for all of the sperm head parameters under consideration. This result demonstrates that the procedures of ®xation and staining signi®cantly affect the dimensions of sperm heads.

Spermatozoa were obtained from nine epididymal regions of six epididymides taken from five men undergoing castration for prostatic carcinoma (53-76 years) and from one man with testicular cancer (38 years). Spermatozoa were obtained by mincing tissue in phosphate-buffered saline, making air dried smears and staining with Hemacolor. The percentage of sperm heads categorised subjectively as normal (of uniform shape) or otherwise was calculated for each region. This confirmed that grossly swollen sperm heads (previously shown to be artefacts) were only present in proximal regions of the duct. A computer-aided sperm morphology analyser (Sperm Class Analyzer(R)) was used to provide objective measurements of sperm head area, perimeter, length and width of the uniform sperm heads and revealed that there was a gradual and statistically significant decline in sperm head size upon maturation, as occurs in other species. There was no significant difference between the morphometric parameters of spermatozoa obtained from the distal cauda epididymis and those obtained from the ejaculates of young normozoospermic patients.

Morphologic and morphometric sperm characteristics of mouse epididymal extracts from animals exposed to static magnetic fields were evaluated. For this purpose, animals were exposed for 35 days to a field of 0.7 T generated by a commercial permanent magnet for either 1 or 24 h per day. The values of morphometric parameters were obtained using the morphometric module of the Sperm Class Analyzer® computerized image analysis system, and percentages of abnormalities were calculated. The size of sperm heads was unaffected by exposure to static magnetic fields. Lack of hook was a sperm head abnormality found significantly more frequently in animals exposed continually than in nonexposed animals, showing a possible alteration to the spermatogenic process after exposure to static magnetic fields. The percentage of sperm with coiled tails or of sperm with abnormal midpiece or tail was not altered by exposure. Bioelectromagnetics 19:377–383, 1998. © 1998 Wiley‐Liss, Inc.

The renin–angiotensin system (RAS), and particularly its angiotensin type-2 receptors (AT2), have been classically involved in processes of cell proliferation and maturation during development. However, the potential role of RAS in adult neurogenesis in the ventricular-subventricular zone (V-SVZ) and its aging-related alterations have not been investigated. In the present study, we analyzed the role of major RAS receptors on neurogenesis in the V-SVZ of adult mice and rats. In mice, we showed that the increase in proliferation of cells in this neurogenic niche was induced by activation of AT2 receptors but depended partially on the AT2-dependent antagonism of AT1 receptor expression, which restricted proliferation. Furthermore, we observed a functional dependence of AT2 receptor actions on Mas receptors. In rats, where the levels of the AT1 relative to those of AT2 receptor are much lower, pharmacological inhibition of the AT1 receptor alone was sufficient in increasing AT2 receptor levels and proliferation in the V-SVZ. Our data revealed that interactions between RAS receptors play a major role in the regulation of V-SVZ neurogenesis, particularly in proliferation, generation of neuroblasts, and migration to the olfactory bulb, both in young and aged brains, and suggest potential beneficial effects of RAS modulators on neurogenesis.