Basic Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2018; 24(35): 4028-4035
Published online Sep 21, 2018. doi: 10.3748/wjg.v24.i35.4028
Adiponectin affects the mechanical responses in strips from the mouse gastric fundus
Eglantina Idrizaj, Rachele Garella, Giovanni Castellini, Hermine Mohr, Natalia S Pellegata, Fabio Francini, Valdo Ricca, Roberta Squecco, Maria Caterina Baccari
Eglantina Idrizaj, Rachele Garella, Fabio Francini, Roberta Squecco, Maria Caterina Baccari, Department of Experimental and Clinical Medicine, Section of Physiological Sciences, University of Florence, Florence 50134, Italy
Giovanni Castellini, Valdo Ricca, Psychiatry Unit, Department of Health Sciences, University of Florence, Florence 50134, Italy
Hermine Mohr, Natalia S Pellegata, Institute for Diabetes and Cancer, Helmholtz Zentrum München, Neuherberg 85764, Germany
Author contributions: Idrizaj E and Garella R contributed equally to this work; Idrizaj E and Garella R performed the functional experiments; Idrizaj E and Mohr H performed the PCR analysis; Castellini G, Ricca V, Squecco R and Baccari MC designed the research study; Pellegata NS and Francini F contributed to design the research study; Idrizaj E, Garella R and Baccari MC analyzed the data; Baccari MC wrote the paper; Idrizaj E, Garella R, Castellini G, Mohr H, Pellegata NS, Francini F, Ricca V, Squecco R and Baccari MC critically revised the manuscript.
Supported by the Florence University (No. RTD CO 090101010107; RICATEN14) and Fondazione CRF (No. 2017.0777).
Institutional animal care and use committee statement: The experimental protocol was designed in compliance with the guidelines of the European Communities Council Directive 2010/63/UE and the recommendations for the care and use of laboratory animals approved by the Animal Care Committee of the University of Florence, Italy, with authorization from the Italian Ministry of Health nr. 787/2016-PR.
Conflict-of-interest statement: No conflicts of interest, financial or otherwise, are declared by the authors.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Maria Caterina Baccari, PhD, Professor, Department of Experimental and Clinical Medicine, Section of Physiological Sciences, University of Florence, Viale G.B. Morgagni 63, Florence 50134, Italy. mcaterina.baccari@unifi.it
Telephone: +39-55-2751600 Fax: +39-55-4379506
Received: June 8, 2018
Peer-review started: June 8, 2018
First decision: July 3, 2018
Revised: July 12, 2018
Accepted: July 22, 2018
Article in press: July 22, 2018
Published online: September 21, 2018
Abstract
AIM

To investigate whether the adipocytes derived hormone adiponectin (ADPN) affects the mechanical responses in strips from the mouse gastric fundus.

METHODS

For functional experiments, gastric strips from the fundal region were cut in the direction of the longitudinal muscle layer and placed in organ baths containing Krebs-Henseleit solution. Mechanical responses were recorded via force-displacement transducers, which were coupled to a polygraph for continuous recording of isometric tension. Electrical field stimulation (EFS) was applied via two platinum wire rings through which the preparation was threaded. The effects of ADPN were investigated on the neurally-induced contractile and relaxant responses elicited by EFS. The expression of ADPN receptors, Adipo-R1 and Adipo-R2, was also evaluated by touchdown-PCR analysis.

RESULTS

In the functional experiments, EFS (4-16 Hz) elicited tetrodotoxin (TTX)-sensitive contractile responses. Addition of ADPN to the bath medium caused a reduction in amplitude of the neurally-induced contractile responses (P < 0.05). The effects of ADPN were no longer observed in the presence of the nitric oxide (NO) synthesis inhibitor L-NG-nitro arginine (L-NNA) (P > 0.05). The direct smooth muscle response to methacholine was not influenced by ADPN (P > 0.05). In carbachol precontracted strips and in the presence of guanethidine, EFS induced relaxant responses. Addition of ADPN to the bath medium, other than causing a slight and progressive decay of the basal tension, increased the amplitude of the neurally-induced relaxant responses (P < 0.05). Touchdown-PCR analysis revealed the expression of both Adipo-R1 and Adipo-R2 in the gastric fundus.

CONCLUSION

The results indicate for the first time that ADPN is able to influence the mechanical responses in strips from the mouse gastric fundus.

Keywords: Adiponectin, Adiponectin receptors, Gastric motility, Nitric oxide, Non-adrenergic, non-cholinergic neurotransmission

Core tip: Evidence exists that some white adipose-tissue derived hormones that are involved in the regulation of food intake also influence the motor responses of the gastrointestinal tract. In this view, adiponectin (ADPN) too has been reported to influence food intake but no data concerning its effects on the gastric mechanical activity are available. The present results indicate for the first time that ADPN is able to influence the mechanical responses in strips from the mouse gastric fundus. It could be speculated that these peripheral effects on motor phenomena might represent an additional mechanism engaged by the hormone to control food intake.