Submitted December 21, 2007
Returned for revision January 29, 2008
Accepted April 24, 2008
Male Reproductive Tract
Effects of the Antiestrogen Fulvestrant (ICI 182,780) on Gene Expression of the Rat Efferent Ductules
Fabiana Yasuhara ,
Gisele Renata Oliveira Gomes ,
Erica Rosanna Siu ,
Cláudia Igushi Suenaga ,
Elisabeth Maróstica ,
Catarina Segreti Porto ,
and
Maria Fatima Magalhaes Lazari *
* To whom correspondence should be addressed. E-mail: lazari{at}farm.epm.br.
Abstract
The efferent ductules express the highest amount of estrogen receptors ESR1 (ERalpha) and ESR2 (ERbeta) within the male reproductive tract. Treatment of rats with the antiestrogen fulvestrant (ICI 182,780) causes inhibition of fluid reabsorption in the efferent ductules, leading to seminiferous tubules atrophy and infertility. To provide a more comprehensive knowledge about the molecular targets for estrogen in the rat efferent ductules we investigated the effects of ICI 182,780 treatment on gene expression using a microarray approach. Treatment with ICI 182,780 increased or reduced at least 2-fold the expression of 263 and 98 genes, respectively. Not surprisingly, several genes that encode ion channels and macromolecule transporters were affected. Interestingly, treatment with ICI 182,780 markedly altered the expression of genes related to extracellular matrix organization. Matrix metalloproteinase 7 (Mmp7), osteopontin (Spp1) and neuronal pentraxin 1 (Nptx1) were among the most altered genes in this category. Up-regulation of Mmp7 and Spp1 and downregulation of Nptx1 were validated by Northern blot. Increase in Mmp7 expression was further confirmed by immunohistochemistry and probably accounted for the decrease in collagen content observed in the efferent ductules of ICI 182,780-treated animals. Down-regulation of Nptx1 probably contributed to the extracellular matrix changes and decreased amyloid deposition in the efferent ductules of ICI 182,780-treated animals. Identification of new molecular targets for estrogen action may help elucidate the regulatory role of this hormone in the male reproductive tract.
Key words:
Male Reproductive Tract •
Estradiol •
Gene regulation •
Efferent ductules
