Influence of three different histological methods on the morphology and morphometrical data in human testis

Coagulant fixatives and paraffin embedding were widely used in the past for histomorphometrical evaluations of the human testis under physiological and pathological conditions. However, new methods are applied nowadays using better combinations of fixatives and plastic resins as embedding media, improving cell and tissue structural preservation. In an attempt to compare old and new data, the present study evaluated histomorphometrical data obtained from human testis after three different histological processing methods: Bouin/paraplast, glutaraldehyde/glycol methacrylate and glutaraldehyde/araldite. The morphometrical parameters were not affected by glutaraldehyde fixation after both resin embedding (methacrylate or araldite). On the other hand, Bouin/paraplast embedding lead to tissue shrinkage, which could give rise to misinterpretations on the measurements performed. Since some germ and somatic cells recognition do not depend upon high resolution techniques, counting of such cell types could be performed even using routine Bouin/paraplast protocols. Thus, the morphometrical analyses relying on cell recognition were not affected by the methods here applied, however, when metric measurements were applied, the obtained results could not be promptly compared. On the other hand, if the study requires confident spermatogonial identification for kinetics evaluation, glutaraldehyde/araldite processing is highly recommended.