Regional differences of tachykinin effects on smooth muscle and pacemaker potentials of the stomach, duodenum, ileum and colon of an emetic model, the house musk shrews
Julia Y.H. Liu , Yingyi Deng , Jessica C.M. Hui , Peng Du , Heidi S.H. Ng , Zengbing Lu , Lingqing Yang , Luping Liu , Aleena Khalid , M.P. Ngan , Dexuan Cui , Bin Jiang , S.W. Chan , John A. Rudd
{"title":"Regional differences of tachykinin effects on smooth muscle and pacemaker potentials of the stomach, duodenum, ileum and colon of an emetic model, the house musk shrews","authors":"Julia Y.H. Liu , Yingyi Deng , Jessica C.M. Hui , Peng Du , Heidi S.H. Ng , Zengbing Lu , Lingqing Yang , Luping Liu , Aleena Khalid , M.P. Ngan , Dexuan Cui , Bin Jiang , S.W. Chan , John A. Rudd","doi":"10.1016/j.npep.2022.102300","DOIUrl":null,"url":null,"abstract":"<div><h3>Background and aims</h3><p>The contractile effects of tachykinins on the gastrointestinal tract are well-known, but how they modulate slow-waves, particularly in species capable of emesis, remains largely unknown. We aimed to elucidate the effects of tachykinins on myoelectric and contractile activity of isolated gastrointestinal tissues of the <em>Suncus murinus</em>.</p></div><div><h3>Methods</h3><p>The effects of substance P (SP), neurokinin (NK)A, NKB and selective NK<sub>1</sub> (CP122,721, CP99,994), NK<sub>2</sub> (SR48,968, GR159,897) and NK<sub>3</sub> (SB218,795, SB222,200) receptor antagonists on isolated stomach, duodenum, ileum and colon segments were studied. Mechanical contractile activity was recorded using isometric force displacement transducers. Electrical pacemaker activity was recorded using a microelectrode array.</p></div><div><h3>Results</h3><p>Compared with NKA, SP induced larger contractions in stomach tissue and smaller contractions in intestinal segments, where oscillation magnitudes increased in intestinal segments, but not the stomach. CP122,721 and GR159,897 inhibited electrical field stimulation-induced contractions of the stomach, ileum and colon. NKB and NK<sub>3</sub> had minor effects on contractile activity. The inhibitory potencies of SP and NKA on the peristaltic frequency of the colon and ileum, respectively, were correlated with those on electrical pacemaker frequency. SP, NKA and NKB inhibited pacemaker activity of the duodenum and ileum, but increased that of the stomach and colon. SP elicited a dose-dependent contradictive pacemaker frequency response in the colon.</p></div><div><h3>Conclusion</h3><p>This study revealed distinct effects of tachykinins on the mechanical and electrical properties of the stomach and colon vs. the proximal intestine, providing a unique aspect on neuromuscular correlation in terms of the effects of tachykinin on peristaltic and pacemaker activity in gastrointestinal-related symptoms.</p></div>","PeriodicalId":19254,"journal":{"name":"Neuropeptides","volume":"97 ","pages":"Article 102300"},"PeriodicalIF":2.5000,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Neuropeptides","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0143417922000750","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENDOCRINOLOGY & METABOLISM","Score":null,"Total":0}
引用次数: 1
Abstract
Background and aims
The contractile effects of tachykinins on the gastrointestinal tract are well-known, but how they modulate slow-waves, particularly in species capable of emesis, remains largely unknown. We aimed to elucidate the effects of tachykinins on myoelectric and contractile activity of isolated gastrointestinal tissues of the Suncus murinus.
Methods
The effects of substance P (SP), neurokinin (NK)A, NKB and selective NK1 (CP122,721, CP99,994), NK2 (SR48,968, GR159,897) and NK3 (SB218,795, SB222,200) receptor antagonists on isolated stomach, duodenum, ileum and colon segments were studied. Mechanical contractile activity was recorded using isometric force displacement transducers. Electrical pacemaker activity was recorded using a microelectrode array.
Results
Compared with NKA, SP induced larger contractions in stomach tissue and smaller contractions in intestinal segments, where oscillation magnitudes increased in intestinal segments, but not the stomach. CP122,721 and GR159,897 inhibited electrical field stimulation-induced contractions of the stomach, ileum and colon. NKB and NK3 had minor effects on contractile activity. The inhibitory potencies of SP and NKA on the peristaltic frequency of the colon and ileum, respectively, were correlated with those on electrical pacemaker frequency. SP, NKA and NKB inhibited pacemaker activity of the duodenum and ileum, but increased that of the stomach and colon. SP elicited a dose-dependent contradictive pacemaker frequency response in the colon.
Conclusion
This study revealed distinct effects of tachykinins on the mechanical and electrical properties of the stomach and colon vs. the proximal intestine, providing a unique aspect on neuromuscular correlation in terms of the effects of tachykinin on peristaltic and pacemaker activity in gastrointestinal-related symptoms.
期刊介绍:
The aim of Neuropeptides is the rapid publication of original research and review articles, dealing with the structure, distribution, actions and functions of peptides in the central and peripheral nervous systems. The explosion of research activity in this field has led to the identification of numerous naturally occurring endogenous peptides which act as neurotransmitters, neuromodulators, or trophic factors, to mediate nervous system functions. Increasing numbers of non-peptide ligands of neuropeptide receptors have been developed, which act as agonists or antagonists in peptidergic systems.
The journal provides a unique opportunity of integrating the many disciplines involved in all neuropeptide research. The journal publishes articles on all aspects of the neuropeptide field, with particular emphasis on gene regulation of peptide expression, peptide receptor subtypes, transgenic and knockout mice with mutations in genes for neuropeptides and peptide receptors, neuroanatomy, physiology, behaviour, neurotrophic factors, preclinical drug evaluation, clinical studies, and clinical trials.