Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
REGULATION OF EPIDIDYMAL EPITHELIAL-CELL FUNCTIONS
Autore:
ROBAIRE B; VIGER RS;
Indirizzi:
MCGILL UNIV,DEPT PHARMACOL & THERAPEUT,3655 DRUMMOND ST MONTREAL PQ H3G 1Y6 CANADA
Titolo Testata:
Biology of reproduction
fascicolo: 2, volume: 52, anno: 1995,
pagine: 226 - 236
SICI:
0006-3363(1995)52:2<226:ROEEF>2.0.ZU;2-V
Fonte:
ISI
Lingua:
ENG
Soggetto:
MESSENGER-RIBONUCLEIC-ACID; SULFATED GLYCOPROTEIN-2 CLUSTERIN; ANDROGEN-BINDING PROTEIN; EFFERENT DUCT LIGATION; STEROID 5-ALPHA-REDUCTASE ISOZYMES; RAT VENTRAL PROSTATE; RETE TESTIS FLUID; 3-ALPHA-HYDROXYSTEROID DEHYDROGENASE; MOLECULAR-CLONING; 3ALPHA-HYDROXYSTEROID DEHYDROGENASE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
71
Recensione:
Indirizzi per estratti:
Citazione:
B. Robaire e R.S. Viger, "REGULATION OF EPIDIDYMAL EPITHELIAL-CELL FUNCTIONS", Biology of reproduction, 52(2), 1995, pp. 226-236

Abstract

It is well established that the epididymis is the site where spermatozoa are matured and stored, but our understanding of the regulation ofepididymal epithelium functions and their effects on spermatozoa is still fairly limited. The most active regulator of epididymal functionsseems to be dihydrotestosterone, the 5 alpha-reduced metabolite of testosterone. Our laboratory has focused on the regulation of 5 alpha-reductase, with studies encompassing its messenger RNA, protein, and enzyme activity. We have also investigated the hormonal regulation and distribution of other specific key proteins found in epididymal epithelial cells that play critical roles in the function of these cells. These proteins include clusterin or sulfated glycoprotein-2 and the glutathione S-transferases (GST). Using complementary experimental approaches, including orchidectomy and hormonal replacement, efferent duct ligation, and developmental studies, we have established that 5 alpha-reductase enzyme activity is present in both nuclear and microsomal fractions; the nuclear enzyme appears almost exclusively in the initial segment of the epididymis. In addition, 5 alpha-reductase activity and themRNAs for both the type 1 and type 2 form of the enzyme are regulateddifferentially with respect to age and site within the epididymis. Immunolocalization of the protein has revealed that it is located in principal cells and that its subcellular location is dependent on the region of the epididymis. These results indicate that there is both transcriptional and post-transcriptional regulation of the expression of 5 alpha-reductase. Clusterin is a hydrophobic protein secreted by Sertoli cells and found in high concentration in the epididymis. This glycoprotein is expressed at its highest levels in the initial segment and caput epididymidis and at very low levels in the corpus and cauda epididymidis of the intact rat, and it exhibits a novel pattern of androgenregulation. In the areas of highest expression, there is no androgen dependence; however, orchidectomy causes a dramatic increase in the message for clusterin, which is suppressible by androgens in the segments where expression is normally lowest. The GSTs are a family of enzymes thought to play a key role in detoxification. Members of the GST family are expressed in a region-dependent manner along the rat epididymis. We have found that the localization of one member of this enzyme family, GST P, or subunit Yp, is selective for basal cells in the corpusand cauda epididymidis. Thus, studies of the various cell types in the epididymal epithelium, and of some of the specific biomarkers contained within these cells, have demonstrated that there is remarkably tight control during development and by hormonal factors. These studies should allow us to acquire further insight into the mechanisms by whichthe epididymal epithelium is regulated.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 23/09/20 alle ore 22:12:12