OBSERVATION ON THE CYCLE OF THE SEMINIFEROUS EPITHELIUM IN THE JAPANESE MACAQUE (MACACA-FUSCATA) USING SEMITHIN SECTIONS

The stages of the cycle of the seminiferous epithelium in the Japanese macaque are investigated using testes fixed by a mixture of formaldeh yde and glutaraldehyde containing picric acid and embedded in a methac rylate resin, Quetol 523M. Sections, 1.0 - 2.0 mu m in thickness, were cut with glass knives and stained with periodic acid-Schiff (PAS) and hematoxylin. Sections from such resin blocks illustrated cellular det ail without structural distortion during the polymerization process. F urthermore, staining affinity with PAS and hematoxylin was excellent. In stained sections, typical germ cell associations were described, ba sed on the nuclear morphology of type A (dark and pale) spermatogonium , type B spermatogonium, various developmental stages of primary sperm atocytes during meiosis, and the development of the acrosomic system. In the Japanese macaque, two different steps of spermatids (steps 3 an d 4) were constantly seen in the same area of the tubular epithelium d uring stage III. Therefore, a classification into ten stages is propos ed for the cycle in this species. Additional characteristics are descr ibed based on the observation of the seminiferous epithelium using sem ithin sections.