Abstract:
The aim of this study was to investigate age-related changes in the morphology of
the peritubular boundary tissue and the testicular capsule of pre-pubertal, pubertal,
and adult Japanese quails. The peritubular boundary tissue and testicular capsule
are involved in the propulsion of spermatozoa from the seminiferous tubules into the
excurrent duct system. In addition, the peritubular boundary tissue is thought to
contribute to the formation of the blood-testis barrier. The use of transmission
electron microscopy, as well as the immunolocalization of key cytoskeletal proteins
revealed that the testicular capsule in the Japanese quail was composed
predominantly of smooth muscle cells with relatively few fibroblasts. Furthermore,
the use of histochemistry demonstrated the presence of collagen and reticular fibres
in the testicular capsule, with a few elastic fibres present only in adult quails. In the current study, the morphology of the peritubular boundary tissue varied with
testicular maturation. The results showed a reduction in the number of peritubular
cell layers surrounding the seminiferous tubules as the birds matured. In addition,
immunohistochemistry revealed age-related changes in the localization of
cytoskeletal and basement membrane proteins.
