909 INDUCTION OF RADIATION-INDUCED ERECTILE DYSFUNCTION OF RAT AFTER PROSTATE-CONFINED MODERN RADIOTHERAPY

Abstract

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research1 Apr 2011909 INDUCTION OF RADIATION-INDUCED ERECTILE DYSFUNCTION OF RAT AFTER PROSTATE-CONFINED MODERN RADIOTHERAPY Masaki Kimura, Hui Yan, Zahid Rabbani, Takefumi Satoh, Shiro Baba, Fang-Fang Yin, Thomas Polascik, Craig Donatucci, Zeljko Vujaskovic, and Bridget Koontz Masaki KimuraMasaki Kimura Durham, NC More articles by this author , Hui YanHui Yan Durham, NC More articles by this author , Zahid RabbaniZahid Rabbani Durham, NC More articles by this author , Takefumi SatohTakefumi Satoh Sagamihara, Japan More articles by this author , Shiro BabaShiro Baba Sagamihara, Japan More articles by this author , Fang-Fang YinFang-Fang Yin Durham, NC More articles by this author , Thomas PolascikThomas Polascik Durham, NC More articles by this author , Craig DonatucciCraig Donatucci Durham, NC More articles by this author , Zeljko VujaskovicZeljko Vujaskovic Durham, NC More articles by this author , and Bridget KoontzBridget Koontz Durham, NC More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.800AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Prostate radiation therapy (RT) is a common treatment for localized prostate cancer. Erectile dysfunction (ED) is a common side effect with significant impact on patient quality of life. The mechanisms of RT-induced ED are unclear, as clinical studies are limited and previous animal models do not model current radiation techniques. In this study, we develop an animal model of radiation-induced erectile dysfunction using image-guided three-dimensional (3-D) conformal radiotherapy and begin investigation of mechanisms of RT induced ED. METHODS 60 young adult male rats aged 70–80 days old were divided into age matched sham and RT groups. For RT group, a single 20 Gy fraction to the prostate was delivered by 3D dynamic conformal arc using NovalisTX stereotactic radiotherapy. Penile bulb, shaft, and testes were excluded from treatment fields. Bioassay and intracavernosal pressure (ICP) measurements were conducted at 2, 4, and 9 weeks following RT and in sham animals. After ICP measurements, penile tissues were harvested and evaluated by H&E staining and immunohistochemistry analysis including endothelial nitric-oxide synthase (eNOS) and anti-alpha smooth muscle actin (ASMA). Additionally, the plasma testosterone level of both groups was analyzed using a testosterone ELISA assay kit. Results were compared between RT and sham groups using the Mann-Whitney rank sum test. RESULTS Bioassay and ICP measurements demonstrate statistically significant time-dependant functional impairment of erectile function at 4 and 9 weeks after RT. Plasma testosterone levels were not different between the two groups at any time point (P=0.30, 0.48, and 0.74, respectively). Additionally, immunohistochemistry revealed that expression levels of ASMA and eNOS significantly decreased in cavernous tissue at 9 weeks after RT (P =0.035 and 0.005). All animals received RT could tolerate extremely well without demonstrable toxicities. CONCLUSIONS Our lab has demonstrated the ability to deliver modern radiation therapy to rat prostate using image-guided stereotactic techniques, with time-dependent development of ED. This method can allow investigation into mechanisms of RT-induced ED and its treatment and prevention. Reduction of smooth muscle content and eNOS expression in un-irradiated cavernous tissue is associated with RT induced ED. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e364 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Masaki Kimura Durham, NC More articles by this author Hui Yan Durham, NC More articles by this author Zahid Rabbani Durham, NC More articles by this author Takefumi Satoh Sagamihara, Japan More articles by this author Shiro Baba Sagamihara, Japan More articles by this author Fang-Fang Yin Durham, NC More articles by this author Thomas Polascik Durham, NC More articles by this author Craig Donatucci Durham, NC More articles by this author Zeljko Vujaskovic Durham, NC More articles by this author Bridget Koontz Durham, NC More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...