Navegando por Palavras-chave "Efferent ductules"
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- ItemSomente MetadadadosEffects of the antiestrogen fulvestrant (ICI 182,780) on gene expression of the rat efferent ductules(Soc Study Reproduction, 2008-09-01) Yasuhara, Fabiana [UNIFESP]; Gomes, Gisele Renata de Oliveira [UNIFESP]; Siu, Erica Rosanna [UNIFESP]; Suenaga, Claudia Igushi [UNIFESP]; Marostica, Elisabeth [UNIFESP]; Porto, Catarina Segreti [UNIFESP]; Lazari, Maria de Fatima Magalhaes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)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 tubule 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. Upregulation 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. Downregulation 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.
- ItemSomente MetadadadosExpression and localization of muscarinic acetylcholine receptor subtypes in rat efferent ductules and epididymis(Springer, 2006-01-01) Siu, Erica Rosanna [UNIFESP]; Yasuhara, Fabiana [UNIFESP]; Marostica, Elisabeth [UNIFESP]; Avellar, Maria Christina Werneck [UNIFESP]; Porto, Catarina Segreti [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The expression of muscarinic acetylcholine receptor (mAChR) subtypes (M-1-M-5) was studied in the rat efferent ductules and epididymis at the mRNA and protein levels. the relative abundance of each mAChR transcript subtype differed depending on the tissue and the epididymal region analyzed. the M-1 mAChR mRNA level was more abundant in the efferent ductules than in the caput and cauda of the epididymis. the M-2 mAChR mRNA level was similar between the efferent ductules and caput of the epididymis and higher in the cauda region. the M-3 mAChR mRNA level was low in the efferent ductules and caput of the epididymis, but high levels were detected in the cauda region. mRNAs for M-4 and M-5 mAChRs were not detected in these tissues. Our studies indicated a variable degree of immunostaining for each mAChR subtype in a cell-type and tissue-specific pattern. M-3 mAChR was detected over the efferent ductule epithelium. M-2 and M-3 mAChRs were observed in the apical region of the ciliated cells. Apical and narrow cells of the initial segment showed distinct staining by M-1 antibody, whereas a supranuclear reaction was noted in the principal cells of the caput of the epididymis. in addition, staining for M-1 and M-2 mAChRs was visible in the apical membrane of some epithelial cells of the cauda region. M-3 mAChR was detected in the peritubular smooth muscle of the efferent ductules and epididymis. Functional studies suggested the involvement of this subtype in epididymal tubule contraction. Thus, the cell-specific expression of the various mAChR subtypes in the efferent ductules and epididymis suggests that these receptors play a role in the modulation of luminal fluid composition and smooth muscle contraction.
- ItemSomente MetadadadosMuscarinic Acetylcholine Receptor Subtypes in the Male Reproductive Tract(Humana Press Inc, 2010-01-01) Avellar, Maria Christina Werneck [UNIFESP]; Siu, Erica Rosanna [UNIFESP]; Yasuhara, Fabiana [UNIFESP]; Marostica, Elisabeth; Porto, Catarina Segreti [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Federal Fluminense (UFF)In mammals, at least five different muscarinic acetylcholine receptor subtypes (mAChRs; M(1)-M(5)) are known to be widely expressed and distributed in different tissues from different species. They mediate distinct physiological functions according to their location and receptor subtype. Multiple events are associated with the regulation of intracellular signaling by mAChRs, and a coordinated balance of the molecular mechanisms governing receptor signaling, desensitization, resensitization, and mitogenic signaling is known to occur in various cell types. Most of the actions of acetylcholine (ACh) in the male reproductive tract are induced by its effects on mAChRs, but the role of specific mAChR subtypes on male reproductive function and fertility are still not well understood. the rat efferent ductules and epididymis are androgen-dependent tissues of the male reproductive tract, with important roles in the process to form a viable and fertile sperm. in the present study, aspects of the expression, localization, and potential function of mAChR subtypes in rat efferent ductules and epididymis are reviewed. Furthermore, evidences for the implication of mAChRs in the regulation of protein synthesis and secretion in these tissues are presented. Taken together, the studies contribute to our understanding about physiological aspects of mAChR and mechanisms by which the cholinergic system affects male reproduction.