Ultrastructural Development Study of Testis in Golden Hamster at Different Postnatal Ages

Abstract

The present study aimed to investigate the ultrastructures of the testis in golden hamster during 1, 14, 28, 42, 60 day of old. Animals were administered an intraperitoneal injection of ketamine at 50 mg/kg and xylazine at 5 mg/kg. Subsequently, the animals were surgically opened, and the testes were excised. The testes were sectioned into small 1 mm³ pieces and immediately fixed in 4% buffered glutaraldehyde for 25 to 30 minutes, after which they were trimmed with a sharp knife. Tissue samples with a thickness of 1-3 mm were obtained and subsequently fixed in glutaraldehyde. Observation of one-day-old specimens revealed a normal testicular structural design, characterized by a basal membrane encircled by myoid cells, along with a variety of spermatogonia of differing shapes and sizes. At 14 days old, the vacuolation of Sertoli cells was more dispersed and abundant. The Leydig cells exhibited spherical and oval nuclei containing testosterone. Primary and secondary spermatocytes were observed at 28 days, with some spermatocytes displaying large corkscrew-shaped vacuoles. At 42 days, the same fine structures were noted as in the previous stage. By 60 days, observations indicated a clear mature stage, with apoptotic cells identified near the spermatogonia. The midpiece of spermatozoa showed an axoneme encircled by an outer dense fibril, surrounded by a dense sheet of mitochondria. The principal tail of spermatozoa was distinctly visible, featuring an axoneme encircled by an outer dense fibril, covered by a fibril sheet, along with two central filaments and nine peripheral pairs of filaments.