Metabolic Syndrome Induced Bladder Cannabinoid Receptor Changes in the Fructose‐Fed Rats. Issue 2 (6th April 2017)

• Record Type: Journal Article
• Authors: CHEN, I‐Hung; CHENG, Juei‐Tang; TONG, Yat‐Ching
• Is Part Of: LUTS. Volume 10:Issue 2(2018)
• Page Start: 198
• Page End: 203
• Publication Date: 2017-04-06
• Subjects: bladder -- cannabinoid receptors -- KATP channel -- metabolic syndrome -- protein kinase A; Urology -- Periodicals; Urologic Diseases -- Periodicals; Urinary Tract Physiological Phenomena -- Periodicals; 616.62
• DOI: 10.1111/luts.12156
• Languages: English
• ISSNs: 1757-5664

Abstract

Abstract : Objectives: To investigate the effect of metabolic syndrome on the bladder cannabinoid receptors 1 and 2 (CB1/CB2) expression and function in the fructose‐fed rats (FR). Methods: Adult male Sprague–Dawley rats were divided into two groups: (i) Control rats fed with normal chow; and (ii) Rats fed with high‐fructose diet (FR) for 9 weeks. The body weight, blood pressure, plasma sugar, insulin, triglyceride and cholesterol were measured. Bladder muscle strips were prepared in organ bath and pre‐contracted with 1 µM/L acetylcholine (ACh) or 50 mM/L KCl. The relaxation responses to CB1/CB2 agonist Bay59‐3047 (0.01–1 µM/L) were recorded. The effects of CB1 antagonist AM251, CB2 antagonist AM630, protein kinase A (PKA) inhibitor H‐89 and ATP‐sensitive potassium channel (KATP ) inhibitor glibenclamide on the Bay59‐3047‐induced response were tested. Western blotting and real‐time polymerase chain reaction (RT‐PCR) analyses were performed for bladder CB1/CB2 receptors. Results: Significant increases of body weight, blood pressure, plasma glucose, insulin, cholesterol and triglyceride levels were found in the FR. Bay59‐3047 reduced ACh and KCl pre‐contracted bladder strip tension in a dose‐dependent fashion. The relaxation responses were significantly decreased in the FR. The Bay59‐3047‐induced relaxation was attenuated by AM251, glibenclamide and H‐89. Western blotting and RT‐PCR showed decreased expressions of FR bladder CB1 and CB2 receptor protein and mRNA. Conclusion: CB1/CB2 receptors mediate rat bladder relaxation through the PKA and KATP pathway. The CB1 receptor may play a more prominent role. The response is decreased in the FR bladder due to reduced expressions of the cannabinoid receptors.