Occurrence and localization of uroguanylin in the aging human prostate.
Uroguanylin, a peptide hormone highly expressed in the gastrointestinal tract, is implicated in the regulation of epithelial salt and water transport processes. Since little is known about a possible role of uroguanylin in the reproductive system, we investigated for the first time the occurrence of this peptide in the human prostate using specimens of benign prostatic hyperplasia. Northern blot analyses detected a single uroguanylin transcript of approximately 600 bp in prostate RNA. The uroguanylin expression was further investigated by reverse transcriptase polymerase chain reaction of prostate RNA with uroguanylin-specific primers. Sequencing of the fragments obtained indicated the presence of a uroguanylin molecule with a sequence identical to its intestinal counterpart. Furthermore, in situ hybridization and immunohistochemistry revealed that uroguanylin mRNA and peptide are confined to epithelial cells of the prostate glands. Comparison with the distribution pattern of immunoreactivity for prostate-specific antigen (PSA) showed a high degree of colocalization of uroguanylin- and PSA-immunoreactive cells. In addition, by western blotting techniques we detected the presence of high molecular weight uroguanylin-immunoreactive material in prostatic fluid. In conclusion, our study indicates that the human prostate glands synthesize and secrete (pro-)uroguanylin. We hypothesize that this hormone may play a novel role in the male reproductive tract.
Maake
Caroline
C
Institute of Anatomy, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland. cmaake@anatom.unizh.ch
Auf der Maur
Franziska
F
Jovanovic
Katarina
K
Reinecke
Manfred
M
Hauri
Dieter
D
John
Hubert
H
D000368:Aged; D000375:Aging / Q000502:physiology*; D015152:Blotting, Northern; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D045265:Natriuretic Peptides; D010455:Peptides / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D011467:Prostate / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000032:analysis / Q000378:metabolism; D011470:Prostatic Hyperplasia / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017423:Sequence Analysis, RNA
D045265:Natriuretic Peptides; D010455:Peptides; D012333:RNA, Messenger; C084362:uroguanylin; D017430:Prostate-Specific Antigen