Nitrergic neuro‐muscular transmission is up‐regulated in patients with diverticulosis. Issue 10 (11th August 2014)

• Record Type: Journal Article
• Authors: Espín, F.; Rofes, L.; Ortega, O.; Clavé, P.; Gallego, D.
• Is Part Of: Neurogastroenterology & motility. Volume 26:Issue 10(2014:Oct.)
• Page Start: 1458
• Page End: 1468
• Publication Date: 2014-08-11
• Subjects: Gastrointestinal system -- Motility -- Periodicals; Gastrointestinal system -- Innervation -- Periodicals; 616.33
• DOI: 10.1111/nmo.12407
• Languages: English
• ISSNs: 1350-1925

Abstract

<abstract abstract-type="main" id="nmo12407-abs-0001"> <title>Abstract</title> <sec id="nmo12407-sec-0001" sec-type="section"> <title>Background</title> <p>Neuro‐transmission impairment could be associated to motility changes observed in patients with diverticular disease. Therefore, the objective was to characterize the inhibitory neuro‐muscular transmission and gene expression changes of the enteric inhibitory pathways in patients with diverticulosis (DS).</p> </sec> <sec id="nmo12407-sec-0002" sec-type="section"> <title>Methods</title> <p>Circular muscle strips from sigmoid colon of patients with DS and controls were studied using the organ bath technique to evaluate spontaneous contractility and enteric motor neurons stimulated by electrical field and qRT‐PCR to assess the expression of nNOS, iNOS, P2Y<sub>1</sub>R and PGP9.5.</p> </sec> <sec id="nmo12407-sec-0003" sec-type="section"> <title>Key Results</title> <p>Patients with DS presented decreased spontaneous rhythmic contractions (SRC) that were significantly enhanced after incubation with L‐NNA (1 mM) and TTX (1 <italic>μ</italic>M), and unaffected by the P2Y<sub>1</sub> antagonist MRS2500 (1 <italic>μ</italic>M). Stimulation on enteric motor neurons caused an increased duration of the latency of OFF‐contractions in DS group (<italic>p</italic> < 0.001), antagonized by L‐NNA and slightly affected by MRS2500 (1 <italic>μ</italic>M). No differences in the IC<sub>50</sub> between controls and DS patients were observed on inhibition of SRC for the NO‐donor sodium nitroprusside (SNP) and the preferential P2Y agonist ADP<italic>β</italic>S. Moreover, nNOS relative expression was also up‐regulated 2.3‐fold in the DS group (<italic>p</italic> < 0.05) whereas there was no significant difference in relative expression of iNOS, P2Y<sub>1</sub>R and the neuronal marker PGP9.5 between groups.</p> </sec> <sec id="nmo12407-sec-0004" sec-type="section"> <title>Conclusions & Inferences</title> <p>Patients with DS presented an over‐expression of nNOS with increased endogenously NO‐mediated responses suggesting enhanced NO‐release. Up‐regulation in the nitrergic pathway in early stages of the disease might play a role in colonic motor disorders associated to diverticular disease.</p> </sec> </abstract>