Table of Contents Author Guidelines Submit a Manuscript
The Scientific World Journal
Volume 2014, Article ID 517836, 6 pages
Research Article

Alteration of Loperamide-Induced Prostate Relaxation in High-Fat Diet-Fed Rats

1Department of Urology, Chi-Mei Medical Center Jiali, Jiali Town, Tainan City, Taiwan
2Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan City, Taiwan
3Institute of Clinical Medical Sciences, College of Medicine, National Cheng Kung University, Tainan City, Taiwan
4Department of Urology, Medical College and Hospital, National Cheng Kung University, Tainan City, Taiwan
5National Cheng Kung University Hospital, 138 Sheng-Li Road, Tainan City 704, Taiwan

Received 10 July 2014; Accepted 30 September 2014; Published 20 November 2014

Academic Editor: Olivier Traxer

Copyright © 2014 Sheng-Lung Hsu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Objective. To investigate the change of loperamide-induced prostate relaxation in rats fed with high-fat diet (HFD). Materials and Methods. Adult male Wistar rats were divided into 2 groups: (1) control rats fed with normal chow and (2) rats fed with HFD for 6 months. The prostate was removed for histology study. Isolated prostate strips were hung in organ bath and precontracted with 1 μmol/L phenylephrine or 50 mmol/L KCl. The relaxation responses to loperamide 0.1 to 10 μmol/L were recorded. Western blotting analyses were performed for prostate μ-opioid receptors (MOR) and ATP-sensitive potassium () channel proteins: sulfonylurea receptor (SUR) and inwardly rectifying potassium channel (Kir) 6.2 subunits. Results. Body weight, prostate weight, plasma levels of glucose, insulin, triglyceride, and cholesterol, as well as systolic blood pressure, were significantly increased in the HFD rats. Histology showed prostatic hyperplasia in the HFD rat prostate. Prostatic relaxation induced by loperamide was markedly reduced in HFD when compared to the control. Protein expressions of MOR, SUR, and Kir 6.2 were decreased in HFD-fed rats. Conclusion. Loperamide-induced prostate relaxation is decreased in HFD rats due to reduced MOR and channel expressions.