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中森 裕之ナカモリ ヒロユキ

所属部署医学研究科細胞生理学分野
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Last Updated :2019/09/19

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論文

  • Descending monoaminergic pathways projecting to the spinal defecation center enhance colorectal motility in rats., Naitou K, Nakamori H, Horii K, Kato K, Horii Y, Shimaoka H, Shiina T, Shimizu Y, American journal of physiology. Gastrointestinal and liver physiology, 315, (4) G631 - G637,   2018年10月, 査読有り
  • Induction of hibernation-like hypothermia by central activation of the A1 adenosine receptor in a non-hibernator, the rat., Shimaoka H, Kawaguchi T, Morikawa K, Sano Y, Naitou K, Nakamori H, Shiina T, Shimizu Y, The journal of physiological sciences : JPS, 68, (4) 425 - 430,   2018年07月, 査読有り
  • Colokinetic effect of somatostatin in the spinal defecation center in rats., Naitou K, Shiina T, Nakamori H, Sano Y, Shimaoka H, Shimizu Y, The journal of physiological sciences : JPS, 68, (3) 243 - 251,   2018年05月, 査読有り
  • Local regulatory mechanism to coordinate colorectal motility in rats., Sawada R, Nakamori H, Naitou K, Horii K, Horii Y, Shimaoka H, Shiina T, Shimizu Y, Physiological reports, 6, (10) ,   2018年05月, 査読有り
  • Exogenous serotonin regulates colorectal motility via the 5-HT2and 5-HT3receptors in the spinal cord of rats, H. Nakamori, K. Naitou, Y. Sano, H. Shimaoka, T. Shiina, Y. Shimizu, Y. Shimizu, Neurogastroenterology and Motility, 30,   2018年03月01日, © 2017 John Wiley & Sons Ltd Background: We previously reported that intrathecal injection of noradrenaline or dopamine causes enhancement of colorectal motility. As these monoamines are neurotransmitters of descending pain inhibitory pathways in the spinal cord, we hypothesized that serotonin, which is one of the neurotransmitters involved in descending pain inhibition, also influences the lumbosacral defecation center. Therefore, we examined whether serotonin acting on the spinal defecation center enhances colorectal motility. Methods: Colorectal intraluminal pressure and propelled liquid volume were recorded in vivo in anesthetized rats. Key Results: Intrathecal injection of serotonin into the L6-S1 spinal cord elicited periodic increases in colorectal intraluminal pressure, being associated with increases in liquid output. Pharmacological experiments revealed that the effect of serotonin is mediated by both 5-HT2and 5-HT3receptors. The serotonin-induced enhancement of colorectal motility was unaffected even after disconnection of the defecation center from supraspinal regions by cutting the T8 spinal cord, while transection of the parasympathetic pelvic nerves prevented the colokinetic effect of serotonin. Finally, we investigated interactions among serotonin, noradrenaline and dopamine. Simultaneous administration of sub-effective doses of these monoamine neurotransmitters into the spinal cord caused propulsive colorectal motility slightly but substantially. Conclusions and Inferences: These results demonstrate that exogenous serotonin acts on 5-HT2and 5-HT3receptors in the lumbosacral defecation center and activates the parasympathetic nervous system to enhance colorectal motility in cooperation with noradrenaline and dopamine.
  • Medullary raphe nuclei activate the lumbosacral defecation center through the descending serotonergic pathway to regulate colorectal motility in rats., Nakamori H, Naitou K, Horii Y, Shimaoka H, Horii K, Sakai H, Yamada A, Furue H, Shiina T, Shimizu Y, American journal of physiology. Gastrointestinal and liver physiology, 314, (3) G341 - G348,   2018年03月, 査読有り
  • Serotonin-induced contractile responses of esophageal smooth muscle in the house musk shrew (Suncus murinus), T. Shiina, K. Naitou, H. Nakamori, Y. Suzuki, K. Horii, Y. Sano, H. Shimaoka, Y. Shimizu, Neurogastroenterology and Motility, 28, 1641 - 1648,   2016年11月01日, © 2016 John Wiley & Sons Ltd Background: Serotonin (5-hydroxytryptamine, 5-HT) is a regulatory factor in motility of the gastrointestinal tract including the esophagus. Although we proposed that vagal cholinergic and mast cell-derived non-cholinergic components including serotonin coordinately shorten the esophagus, the precise mechanism of serotonin-induced contractions in the suncus esophagus is still unclear. Therefore, the aims of this study were to determine characteristics of contractile responses induced by serotonin and to identify 5-HT receptor subtypes responsible for regulating motility in the suncus esophagus. Methods: An isolated segment of the suncus esophagus was placed in an organ bath, and longitudinal or circular mechanical responses were recorded using a force transducer. Key Results: Serotonin evoked contractile responses of the suncus esophagus in the longitudinal direction but not in the circular direction. Tetrodotoxin did not affect the serotonin-induced contractions. Pretreatment with a non-selective 5-HT receptor antagonist or double application of 5-HT1and 5-HT2receptor antagonists blocked the serotonin-induced contractions. 5-HT1and 5-HT2receptor agonists, but not a 5-HT3receptor agonist, evoked contractile responses in the suncus esophagus. Conclusion & Inferences: The findings suggest that serotonin induces contractile responses of the longitudinal smooth muscle in the muscularis mucosae of the suncus esophagus that are mediated via 5-HT1and 5-HT2receptors on muscle cells. The serotonin-induced contractions might contribute to esophageal peristalsis and emetic response.
  • Stimulation of dopamine D2-like receptors in the lumbosacral defaecation centre causes propulsive colorectal contractions in rats., Naitou K, Nakamori H, Shiina T, Ikeda A, Nozue Y, Sano Y, Yokoyama T, Yamamoto Y, Yamada A, Akimoto N, Furue H, Shimizu Y, The Journal of physiology, 594, (15) 4339 - 4350,   2016年08月, 査読有り
  • Does the capsaicin-sensitive local neural circuit constitutively regulate vagally evoked esophageal striated muscle contraction in rats?, Shima T, Shiina T, Naitou K, Nakamori H, Sano Y, Shimizu Y, The journal of physiological sciences : JPS, 66, (2) 105 - 111,   2016年03月, 査読有り
  • Inhibitory action of hydrogen sulfide on esophageal striated muscle motility in rats., Shiina T, Shima T, Horii K, Naitou K, Nakamori H, Sano Y, Shimizu Y, European journal of pharmacology, 771, 123 - 129,   2016年01月, 査読有り
  • Hibernation-specific alternative splicing of the mRNA encoding cold-inducible RNA-binding protein in the hearts of hamsters., Sano Y, Shiina T, Naitou K, Nakamori H, Shimizu Y, Biochemical and biophysical research communications, 462, (4) 322 - 325,   2015年07月, 査読有り
  • Colokinetic effect of noradrenaline in the spinal defecation center: implication for motility disorders., Naitou K, Shiina T, Kato K, Nakamori H, Sano Y, Shimizu Y, Scientific reports, 5,   2015年07月, 査読有り
  • Regulation of longitudinal esophageal motility in the house musk shrew (Suncus murinus)., Shiina T, Naitou K, Nakamori H, Sakai H, Shimizu Y, Autonomic neuroscience : basic & clinical, 189, 37 - 42,   2015年05月, 査読有り
  • Characterization of ghrelin-sensitive neurons in the lumbosacral defecation center in rats, K. Naitou, T. Shiina, R. Sugita, H. Nakamori, Y. Shimizu, Neurogastroenterology and Motility, 27, 147 - 155,   2015年01月01日, © 2014 John Wiley & Sons Ltd. Background: Ghrelin is involved in the regulation of somatic growth, feeding behavior and energy homeostasis. Ghrelin stimulates neuropeptide Y (NPY) neurons and activates intracellular AMP-activated protein kinase (AMPK) in the hypothalamus. These NPY neurons also express the leptin receptor and leptin inhibits ghrelin-induced activation of NPY neurons. In the spinal cord, we have demonstrated colokinetic action of ghrelin. However, the precise characteristics of the ghrelin-sensitive neurons remain to be clarified. The aim of this study was firstly to confirm that the action of ghrelin is mediated via a neurogenic pathway in the spinal cord, and secondly to characterize the ghrelin-sensitive neurons by comparing with hypothalamic ghrelin-sensitive neurons. Methods: Rats were anesthetised with alpha-chloralose and ketamine, and colorectal intraluminal puressure and expelled volume were recorded in vivo. Drugs were applied intrathecally. Key Results: Ghrelin caused enhancement of propulsive contractions. Tetrodotoxin completely blocked the colokinetic effect of ghrelin. An AMPK activator, aminoimidazole carboxamide ribonucleotide, failed to mimic the ghrelin effect. Leptin had no effect on the spontanious contractions and did not exert a suppressive effect on the ghrelin-enhanced colorectal motility. An NPY Y1 receptor antagonist did not affect the action of ghrelin. NPY had no effect on the colorectal motility. Conclusions & Inferences: This study showed that intrathecal injection of ghrelin stimulates colorectal motility by acting on ghrelin-sensitive neurons in the lumbosacral defecation center. The characteristics of ghrelin-sensitive neurons in the spinal cord are quite different from those of ghrelin-sensitive neurons in the hypothalamus.
  • Actions of probiotics on trinitrobenzenesulfonic acid-induced colitis in rats., Shiina T, Shima T, Naitou K, Nakamori H, Sano Y, Horii K, Shimakawa M, Ohno H, Shimizu Y, BioMed research international, 2015,   2015年, 査読有り
  • Functional roles of capsaicin-sensitive intrinsic neural circuit in the regulation of esophageal peristalsis in rats: in vivo studies using a novel method., Shima T, Shiina T, Naitou K, Nakamori H, Shimizu Y, American journal of physiology. Gastrointestinal and liver physiology, 306, (9) G811 - 8,   2014年05月, 査読有り


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