Role of Estrogens in the Male Reproductive Tract
Most of the studies associated with defining the effects of estrogen have relied upon the use of models in which exogenous estrogens [17β-estradiol or diethylstilbestrol (DES)] are administered to rodents (Raijfer and Coffey 1979; vom Saal et al. 1997; Prins 1992; Pylkkanen et al. 1991, 1993; Prins and Birch 1997; Singh and Han-delsman 1999), from which conflicting outcomes have been reported (vom Saal et al. 1997; Prins 1992; Prins and Birch 1995). The creation of knockout mice (ArKO), in which the Cyp19 gene, encoding the aromatase enzyme, is disrupted (Fisher et al. 1998), provides a means to study the long-term effects of endogenous estrogen withdrawal in the male in vivo and to examine the effects on spermatogenesis and prostatic growth. Increasing evidence suggests a crucial role for estrogens in the development and function of male reproductive structures.
KeywordsGerm Cell Seminiferous Tubule Round Spermatid RNase Protection Assay Germ Cell Development
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