title: Bariatric surgery improves the cavernosal neuronal, vasorelaxation, and contraction mechanisms for erectile dysfunction as result of amelioration of glucose homeostasis in a diabetic rat model.
abstract: BACKGROUND
  Bariatric surgery is an effective treatment option for both obesity and obesity-related type 2 diabetes mellitus (T2DM). However, little is known regarding the effects of bariatric surgery on erectile dysfunction among patients with T2DM. Therefore, we investigated whether bariatric surgery would lead to structural and biochemical changes in the corpus cavernosum.
  
  
  METHODS
  Twenty-five male Otsuka Long-Evans Tokushima Fatty rats were assigned to either a control group (sham operation, n = 10) or a bariatric surgery group (gastric bypass surgery, n = 15). Four weeks after the operation, each group of rats was evaluated with an oral glucose tolerance test (OGTT). The penile intracavernous pressure was measured for erectile functional analysis. Histologic evaluation of the tissue was performed with Masson's trichrome staining. Endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), Rho kinase, and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels in the corpus cavernosum were assayed by using western blot and ELISA.
  
  
  RESULTS
  The mean body weight of the bariatric surgery group was lower than the control group (p = 0.002). The postoperative OGTT result was lower in the bariatric surgery group than in the control group (p = 0.014), and this was lower than the preoperative value (p = 0.037). The intracavernous pressure/mean arterial pressure ratio was higher in the bariatric surgery group compared to the control group (p = 0.021), and a higher cavernosum smooth muscle/collagen ratio was observed in the bariatric surgery group compared to the control group (p = 0.025). Likewise, the expression of eNOS and nNOS was higher in bariatric surgery group than in the control group (p = 0.027 and p = 0.008, respectively). Decreased expression of Rho kinase and levels of 8-OHdG were observed in the bariatric surgery group (p = 0.032).
  
  
  CONCLUSIONS
  In this animal model, bariatric surgery appears to ameliorate T2DM-related metabolic dysfunction leading to structural and biochemical changes in the corpus cavernosum, and thus, results in improvement of erectile dysfunction associated with T2DM.
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Yong Sun
authors.initials: YS
authors.lastname: Choi
authors.affiliation: Department of Surgery, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sang Kuon
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Woong Jin
authors.initials: WJ
authors.lastname: Bae
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hyuk Jin
authors.initials: HJ
authors.lastname: Cho
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sung-Hoo
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Ji Youl
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Tae-Kon
authors.initials: TK
authors.lastname: Hwang
authors.affiliation: Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sae Woong
authors.initials: SW
authors.lastname: Kim
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001835:Body Weight; D003094:Collagen / Q000235:genetics / Q000378:metabolism; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery; D007172:Erectile Dysfunction / Q000150:complications / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery*; D015390:Gastric Bypass; D015870:Gene Expression; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006706:Homeostasis; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D052248:Nitric Oxide Synthase Type I / Q000235:genetics / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D010410:Penile Erection / Q000502:physiology; D010413:Penis / Q000098:blood supply / Q000378:metabolism / Q000503:physiopathology*; D051381:Rats; D020334:Rats, Inbred OLETF; D014664:Vasodilation / Q000502:physiology; D054460:rho-Associated Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003094:Collagen; D052248:Nitric Oxide Synthase Type I; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D054460:rho-Associated Kinases; D003849:Deoxyguanosine; D005947:Glucose