Spermatogenetic clones developing from repopulating stem cells surviving a high dose of an alkylating agent.

摘要: We investigated stem cell renewal and differentiation in 10- 15-days-old spermatogonial clones developing mouse seminiferous epithelium after an extremely large loss, inflicted by high doses of the alkylating agent Myleran. The arise from cells that resemble Ais spermatogonia but have a larger nuclear diameter. In spite their mitotic activity these ‘re-populating cells’ lie mainly isolated or pairs. This is explained migration differentiation. Migration appeared to occur at random all directions along basement membrane tubule. After one more divisions cells, second type appears, which called ‘differentiating spermatogonium’. The time elapsing before this depends on dose Myleran: later starts. A relation could be demonstrated between stage cycle start Differentiating were found groups two, four, eight sixteen cells. Hence we concluded least up fourth division differentiating divide synchronously without degenerations. Three types repopulating distinguished, producing (1) two (2) starting differentiation, (3) Type 1 most frequently.