906 ANDROGEN RECEPTOR LEVELS AND CAG REPEAT NUMBER SIGNIFICANTLY DIFFER BETWEEN MEN WITH POST-PROSTATECTOMY AND ORGANIC ERECTILE DYSFUNCTION

Abstract

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research1 Apr 2011906 ANDROGEN RECEPTOR LEVELS AND CAG REPEAT NUMBER SIGNIFICANTLY DIFFER BETWEEN MEN WITH POST-PROSTATECTOMY AND ORGANIC ERECTILE DYSFUNCTION Alexander W. Pastuszak, Lianqing Yang, Osama Mohamed, Larry I. Lipshultz, and Mohit Khera Alexander W. PastuszakAlexander W. Pastuszak Houston, TX More articles by this author , Lianqing YangLianqing Yang Houston, TX More articles by this author , Osama MohamedOsama Mohamed Houston, TX More articles by this author , Larry I. LipshultzLarry I. Lipshultz Houston, TX More articles by this author , and Mohit KheraMohit Khera Houston, TX More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.797AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The androgen receptor (AR) plays an essential role in penile erectile function. AR activity has recently been shown to be dependent in part on the number of glutamine (CAG) repeats at the N-terminus, with longer repeats being associated with reduced AR activity and weaker transcriptional potential (1). However, few data are available assessing androgen receptor (AR) levels from corporal tissue, and the relationship between AR levels and CAG repeats in this penile tissue from men with erectile dysfunction (ED) remains to be determined. Here we confirm the presence and evaluate the amounts of AR and several of its substrates in men with organic (OED) and post-prostatectomy ED (PPED), and correlate these findings with the number of CAG repeats in the AR. METHODS Twenty-nine men were studied when undergoing penile prosthesis placement, 17 with PPED and 12 with OED. Penile corporal tissue was harvested during penile prosthesis placement and AR levels assessed using Western blot and immunohistochemistry. Levels of cavernosal testosterone (T), dihydrotestosterone (DHT), and 5α-reductase 2 (5AR2) were also measured. The number of CAG repeats within exon 1 of the AR was determined and compared within the two study groups. RESULTS AR and DHT levels were significantly higher in cavernosal tissue from PPED patients as compared to OED patients. (P=0.015 and P=0.015, respectively). There were no significant differences in cavernosal T and 5AR2 levels between the two groups. CAG repeat length was significantly higher in men with OED when compared with men with PPED (28.6 vs. 23.2 repeats, respectively, P=0.03). Immunohistochemical staining demonstrated a significantly higher percentage of AR+ cells in tissue from PPED patients (60.9% PPED AR+ vs. 41.4% OED AR+, P<0.001), and tissue from PPED patients yielded more smooth muscle than tissue from OED patients. CONCLUSIONS Higher levels of cavernosal AR and DHT are found in PPED patients when compared to OED patients, and the number of CAG repeats is significantly lower in men with PPED vs. OED. The amount of corporal smooth muscle appears to be higher in PPED patients. Taken together, these data suggest that men with PPED have a greater quantity of functional penile tissue, as well as an AR that is more likely to respond to hormonal stimulus. References 1 : Effect of a short CAG (glutamine) repeat on human androgen receptor function. Prostate2004; 58: 23. Google Scholar © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e363 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Alexander W. Pastuszak Houston, TX More articles by this author Lianqing Yang Houston, TX More articles by this author Osama Mohamed Houston, TX More articles by this author Larry I. Lipshultz Houston, TX More articles by this author Mohit Khera Houston, TX More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...