The male reproductive system of the non-human primate

Test article—related effects on the male reproductive system can have a profound impact on pharmaceutical development. In NHPs, the assessment of the male reproductive system often occurs by the study pathologist in the context of a repeated-dose general toxicology study rather than in stand-alone developmental and reproductive toxicology studies. This requires the pathologist to have a thorough understanding of endocrinology, spermatogenesis, spontaneous findings, and response to injury. This chapter provides the pathologist with an overview of the normal anatomy, histology, and endocrinology of the male reproductive system along with detailed descriptions and photomicrographs of common spontaneous and xenobiotic-induced changes in order to provide a guide for both new and experienced pathologists tasked with evaluating this complicated organ system.