Hiroki Ito1, Naoki Aizawa2, Yasunori Fujita3, Motofumi Suzuki4, Hiroshi Fukuhara4, Yukio Homma4, Yoshinobu Kubota5, Masafumi Ito3, Karl-Erik Andersson6, Yasuhiko Igawa7. 1. Department of Continence Medicine, University of Tokyo Graduate School of Medicine, Tokyo, Japan; Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan. 2. Department of Continence Medicine, University of Tokyo Graduate School of Medicine, Tokyo, Japan. 3. Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan. 4. Department of Urology, University of Tokyo Graduate School of Medicine, Tokyo, Japan. 5. Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan. 6. Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark. 7. Department of Continence Medicine, University of Tokyo Graduate School of Medicine, Tokyo, Japan. Electronic address: yigawa-jua@umin.ac.jp.
Abstract
PURPOSE: Bladder function is often impaired with aging. In other organs caloric restriction has had a prophylactic effect on the biological changes associated with aging. We tested the hypothesis that long-term caloric restriction can prevent age related impaired bladder function in the rat. MATERIALS AND METHODS: Fisher 344 male rats were divided into 3 groups, including 16 young rats at age 6 months with free access to normal food, 15 old rats at age 25 to 28 months with free access to normal food and 16 old rats at age 25 to 28 months fed with normal food 3 days per week since age 6 weeks (caloric restriction). We performed frequency volume measurements, in vitro organ bath functional studies using full-thickness longitudinal detrusor strips, evaluation of muscarinic and purinergic receptor mRNA expression, and histological examination with Masson trichrome staining of bladder tissue. RESULTS: Frequency volume changes did not significantly differ among the 3 groups. The old group fed normal food showed weaker contractile responses to carbachol and electrical field stimulation (especially in the cholinergic component), lower M3 receptor mRNA expression and higher collagen deposition compared to the young group. These age related bladder changes were milder in the old group with caloric restriction than in the old group fed normal food. CONCLUSIONS: This study suggests that in the rat long-term caloric restriction has a preventive effect against age related functional and morphological bladder changes. These changes include impaired detrusor contractility that may be related to decreased expression of M3 receptors and to bladder wall fibrosis.
PURPOSE: Bladder function is often impaired with aging. In other organs caloric restriction has had a prophylactic effect on the biological changes associated with aging. We tested the hypothesis that long-term caloric restriction can prevent age related impaired bladder function in the rat. MATERIALS AND METHODS: Fisher 344 male rats were divided into 3 groups, including 16 young rats at age 6 months with free access to normal food, 15 old rats at age 25 to 28 months with free access to normal food and 16 old rats at age 25 to 28 months fed with normal food 3 days per week since age 6 weeks (caloric restriction). We performed frequency volume measurements, in vitro organ bath functional studies using full-thickness longitudinal detrusor strips, evaluation of muscarinic and purinergic receptor mRNA expression, and histological examination with Masson trichrome staining of bladder tissue. RESULTS: Frequency volume changes did not significantly differ among the 3 groups. The old group fed normal food showed weaker contractile responses to carbachol and electrical field stimulation (especially in the cholinergic component), lower M3 receptor mRNA expression and higher collagen deposition compared to the young group. These age related bladder changes were milder in the old group with caloric restriction than in the old group fed normal food. CONCLUSIONS: This study suggests that in the rat long-term caloric restriction has a preventive effect against age related functional and morphological bladder changes. These changes include impaired detrusor contractility that may be related to decreased expression of M3 receptors and to bladder wall fibrosis.
Authors: Hiroki Ito; Anthony E Pickering; Yasuhiko Igawa; Anthony J Kanai; Christopher H Fry; Marcus J Drake Journal: Front Physiol Date: 2017-02-06 Impact factor: 4.566