AIMTo determine the involvement of apoptotic cell death in postnatal pathogenesis in mutant strain of hypogonadic (hgn/hgn) rats testes. We evaluated the numbers and types of cells undergoing apoptotic cell death.

METHODSTissue sections were stained by the TUNEL method for in situ detection of apoptotic cells, with specific antibodies used as markers of testicular somatic and germ cells.

RESULTSWe found that apoptosis in the hgn/hgn testes during the early postnatal period occurred primarily in Sertoli cells, which should actively proliferate during this stage of differentiation. These findings strongly suggest that the normal allele of hgn is involved in the direct or indirect control of differentiation and proliferation of Sertoli cells.

CONCLUSIONTo our knowledge, this is the first report demonstrating early postnatal apoptosis of Sertoli cells, suggesting that the hgn/hgn rat is a unique model for the study of Sertoli cell deficiency.