Stereology as a valuable tool in the toolbox of testicular research

The morphology of the testis may be altered in various developmental, physiological and pathological conditions and these changes are reflected by the alterations in the reproductive capacity. Studying testicular morphology under these conditions or following therapeutic interventions relies on quantitative data. Design-based stereology provides quantitative morphological data on the most important characteristics of the testis. The total volume of the testis, seminiferous tubules, interstitial tissues and germinal epithelium, length, diameter and cross sectional area of the tubules as well as the number of Sertoli, Leydig, myoid cells, spermatogonia, spermatocytes and spermatids can be estimated. The present paper explains and demonstrates accurate and efficient stereological methods of sampling and analysis of testicular specimens according to the basics made by the pioneer stereologists. Second-order stereology can provide additional information on the spatial arrangement of the content of the tissues, cells or organelles in testis. These methods are valuable enough to be included in the toolbox of testicular research and are essential whenever quantitative data on morphological characteristics of the testis are required including testicular biopsy of human or in experimental studies.