Spermatogenesis parameters and testosterone production at puberty as predictors of testicular functional activity in mice (Mus musculus)

Аннотация

The aim of this study was to investigate fertility-associated parameters of spermatogenesis and androgenic status in male laboratory mice at puberty and to assess their prognostic significance in the realization of the definitive testicular function. In three inbred murine strains, BALB/cLac, CBA/Lac and PT, the serum testosterone level, its testicular concentration, epididymal sperm count (sperm reserve) and portion of sperm with abnormal head morphology were evaluated on days 45 (puberty) and 90 (adulthood) of postnatal development. CBA/Lac males were characterized by a lower epididymal sperm count vs. other strains at both ages indicative of poorer spermatogenesis. At the same time, CBA/Lac males had a lower portion of sperm with abnormal head morphology, and this could be considered as a compensatory reaction aimed at improving sperm fertility. Distinct inter-strain differences in the portion of sperm with morphologically abnormal heads were established at both ages, while the inter-strain ratio remained invariable (BALB/cLac > PT > CBA/Lac). Thus, the level of abnormal spermatogenesis in the pubertal period may have a predictive significance for the definitive testicular activity in adult mice. No inter-strain and age-dependent changes were found in serum and testicular testosterone levels except for the PT strain, in which both testosterone levels rose from puberty to adulthood, suggesting a shift of the pubertal testosterone peak towards later times. Our data show that in male laboratory mice the genetic peculiarities of the testicular function manifest themselves during puberty and persist until adulthood.