Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine

Jingbo Zhao,1 Jian Yang,1 Donghua Liao,1 Hans Gregersen2 1Giome Academia, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 2Giome Center, Department of Surgery, Chinese University of Hong Kong and Prince of Wales Hospital, Shatin, Hong Kong Background: Gastrointestinal disorders...

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Main Authors: Zhao J, Yang J, Liao D, Gregersen H
Format: Article
Language:English
Published: Dove Medical Press 2017-12-01
Series:Clinical and Experimental Gastroenterology
Subjects:
Online Access:https://www.dovepress.com/interdependency-between-mechanical-parameters-and-afferent-nerve-disch-peer-reviewed-article-CEG
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author Zhao J
Yang J
Liao D
Gregersen H
author_facet Zhao J
Yang J
Liao D
Gregersen H
author_sort Zhao J
collection DOAJ
description Jingbo Zhao,1 Jian Yang,1 Donghua Liao,1 Hans Gregersen2 1Giome Academia, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 2Giome Center, Department of Surgery, Chinese University of Hong Kong and Prince of Wales Hospital, Shatin, Hong Kong Background: Gastrointestinal disorders are very common in diabetic patients, but the pathogenesis is still not well understood. Peripheral afferent nerves may be involved due to the complex regulation of gastrointestinal function by the enteric nervous system. Objective: We aimed to characterize the stimulus–response function of afferent fibers innervating the jejunum in the Goto-Kakizaki (GK) type 2 diabetic rat model. A key question is whether changes in afferent firing arise from remodeled tissue or from adaptive afferent processes. Design: Seven 32-week-old male GK rats and seven age-matched normal Wistar rats were studied. Firing from mesenteric afferent nerves was recorded in excised jejunal segments of seven GK rats and seven normal Wistar rats during ramp test, stress relaxation test, and creep test. The circumferential stress–strain, spike rate increase ratio (SRIR), and single unit firing rates were calculated for evaluation of interdependency of the mechanical stimulations and the afferent nerve discharge. Results: Elevated sensitivity to mechanical stimuli was found for diabetic nerve bundles and single unit activity (P<0.05). The stress relaxed less in the diabetic intestinal segment (P<0.05). Linear association between SRIR and the thickness of circumferential muscle layer was found at high stress levels as well as for SRIR and the glucose level. Conclusion: Altered viscoelastic properties and elevated mechanosensitivity were found in the GK rat intestine. The altered nerve signaling is related to muscle layer remodeling and glucose levels and may contribute to gastrointestinal symptoms experienced by diabetic patients. Keywords: afferents, spike rate, stress–strain, creep, stress relaxation, small intestine, type 2 diabetes 
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spelling doaj.art-ecad6fe2b4ef4a1daff490a1c1204ba02022-12-22T02:52:22ZengDove Medical PressClinical and Experimental Gastroenterology1178-70232017-12-01Volume 1030331435809Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestineZhao JYang JLiao DGregersen HJingbo Zhao,1 Jian Yang,1 Donghua Liao,1 Hans Gregersen2 1Giome Academia, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 2Giome Center, Department of Surgery, Chinese University of Hong Kong and Prince of Wales Hospital, Shatin, Hong Kong Background: Gastrointestinal disorders are very common in diabetic patients, but the pathogenesis is still not well understood. Peripheral afferent nerves may be involved due to the complex regulation of gastrointestinal function by the enteric nervous system. Objective: We aimed to characterize the stimulus–response function of afferent fibers innervating the jejunum in the Goto-Kakizaki (GK) type 2 diabetic rat model. A key question is whether changes in afferent firing arise from remodeled tissue or from adaptive afferent processes. Design: Seven 32-week-old male GK rats and seven age-matched normal Wistar rats were studied. Firing from mesenteric afferent nerves was recorded in excised jejunal segments of seven GK rats and seven normal Wistar rats during ramp test, stress relaxation test, and creep test. The circumferential stress–strain, spike rate increase ratio (SRIR), and single unit firing rates were calculated for evaluation of interdependency of the mechanical stimulations and the afferent nerve discharge. Results: Elevated sensitivity to mechanical stimuli was found for diabetic nerve bundles and single unit activity (P<0.05). The stress relaxed less in the diabetic intestinal segment (P<0.05). Linear association between SRIR and the thickness of circumferential muscle layer was found at high stress levels as well as for SRIR and the glucose level. Conclusion: Altered viscoelastic properties and elevated mechanosensitivity were found in the GK rat intestine. The altered nerve signaling is related to muscle layer remodeling and glucose levels and may contribute to gastrointestinal symptoms experienced by diabetic patients. Keywords: afferents, spike rate, stress–strain, creep, stress relaxation, small intestine, type 2 diabetes https://www.dovepress.com/interdependency-between-mechanical-parameters-and-afferent-nerve-disch-peer-reviewed-article-CEGAfferentsSpike rateStress-strainCreepStress-relaxationSmall intestineType 2 diabetes
spellingShingle Zhao J
Yang J
Liao D
Gregersen H
Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
Clinical and Experimental Gastroenterology
Afferents
Spike rate
Stress-strain
Creep
Stress-relaxation
Small intestine
Type 2 diabetes
title Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
title_full Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
title_fullStr Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
title_full_unstemmed Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
title_short Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine
title_sort interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic goto kakizaki rat intestine
topic Afferents
Spike rate
Stress-strain
Creep
Stress-relaxation
Small intestine
Type 2 diabetes
url https://www.dovepress.com/interdependency-between-mechanical-parameters-and-afferent-nerve-disch-peer-reviewed-article-CEG
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