title: Fat deposition in the tunica muscularis and decrease of interstitial cells of Cajal and nNOS-positive neuronal cells in the aged rat colon.
abstract: Little is known about the time course of aging on interstitial cells of Cajal (ICC) of colon. The aim of this study was to investigate the change of morphology, ICC, and neuronal nitric oxide synthase (nNOS)-immunoreactive cells in the aged rat. The proximal colon of 344 Fischer rats at four different ages (6, 31, 74 wk, and 2 yr) were studied. The immunoreactivity of c-Kit, nNOS, anti-protein gene product 9.5, and synaptophysin were counted after immunohistochemistry. The c-kit, stem cell factor (ligand of Kit), and nNOS mRNA were measured by real-time PCR. c-Kit and nNOS protein were assessed by Western blot. Isovolumetric contractile force measurement and electrical field stimulation (EFS) were conducted. The area of intramuscular fat deposition significantly increased with age after 31 wk. c-Kit-immunoreactive ICC and nNOS-immunoreactive neurons and nerve fibers significantly declined with age. mRNA and protein expression of c-kit and nNOS decreased with aging. The functional study showed that the spontaneous contractility was decreased in aged rat, whereas EFS responses in the presence of atropine and L-NG-Nitroarginine methyl ester were increased in aged rat. In conclusion, the decrease of proportion of proper smooth muscle, the density of ICC and nNOS-immunoreactive neuronal fibers, and the number of nNOS-immunoreactive neurons during the aging process may explain the aging-associated colonic dysmotility.
authors: Departments of Internal Medicine and.
authors: Hyun Jin
authors: HJ
authors: Jo
authors: Nayoung
authors: N
authors: Kim
authors: Ryoung Hee
authors: RH
authors: Nam
authors: Jung Mook
authors: JM
authors: Kang
authors: Joo-Hyon
authors: JH
authors: Kim
authors: Gheeyoung
authors: G
authors: Choe
authors: Hye Seung
authors: HS
authors: Lee
authors: Ji Hyun
authors: JH
authors: Park
authors: Hyun
authors: H
authors: Chang
authors: Hyunjin
authors: H
authors: Kim
authors: Moon Young
authors: MY
authors: Lee
authors: Yong Sung
authors: YS
authors: Kim
authors: Joo Sung
authors: JS
authors: Kim
authors: Hyun Chae
authors: HC
authors: Jung
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism / Q000473:pathology; D000375:Aging / Q000378:metabolism*; D000818:Animals; D016922:Cellular Senescence / Q000502:physiology; D003106:Colon / Q000378:metabolism / Q000473:pathology; D017615:Enteric Nervous System / Q000378:metabolism*; D005769:Gastrointestinal Motility / Q000502:physiology; D007150:Immunohistochemistry; D056885:Interstitial Cells of Cajal / Q000378:metabolism*; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000378:metabolism / Q000473:pathology; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D019089:Stem Cell Factor / Q000378:metabolism
chemical_list: D019089:Stem Cell Factor; D052248:Nitric Oxide Synthase Type I; D019009:Proto-Oncogene Proteins c-kit
keywords: aging; colon; inbred F344; interstitial cells of Cajal; neuronal nitric oxide synthase; rats