The Journal of Physiological Sciences

, Volume 69, Issue 1, pp 129–141 | Cite as

The inhibitory role of purinergic P2Y receptor on Mg2+ transport across intestinal epithelium-like Caco-2 monolayer

  • Narongrit ThongonEmail author
  • Siriporn Chamniansawat
Original Paper


The mechanism of proton pump inhibitors (PPIs) suppressing intestinal Mg2+ uptake is unknown. The present study aimed to investigate the role of purinergic P2Y receptors in the regulation of Mg2+ absorption in normal and omeprazole-treated intestinal epithelium-like Caco-2 monolayers. Omeprazole suppressed Mg2+ transport across Caco-2 monolayers. An agonist of the P2Y2 receptor, but not the P2Y4 or P2Y6 receptor, suppressed Mg2+ transport across control and omeprazole-treated monolayers. Omeprazole enhanced P2Y2 receptor expression in Caco-2 cells. Forskolin and P2Y2 receptor agonist markedly enhanced apical HCO3 secretion by control and omeprazole-treated monolayers. The P2Y2 receptor agonist suppressed Mg2+ transport and stimulated apical HCO3 secretion through the Gq-protein coupled-phospholipase C (PLC) dependent pathway. Antagonists of cystic fibrosis transmembrane conductance regulator (CFTR) and Na+-HCO3 cotransporter-1 (NBCe1) could nullify the inhibitory effect of P2Y2 receptor agonist on Mg2+ transport across control and omeprazole-treated Caco-2 monolayers. Our results propose an inhibitory role of P2Y2 on intestinal Mg2+ absorption.


Caco-2 monolayers Intestinal HCO3 secretion Mg2+ absorption Proton pump inhibitor P2Y2 receptor 



This study was supported by research grants from Burapha University through the National Research Council of Thailand (138/2560), and the Faculty of Allied Health Sciences, Burapha University (AHS06/2560) to N. Thongon. We express our gratitude to Dr. Prasert Sobhon of the Faculty of Allied Health Sciences, Burapha University for his helpful suggestions and proofreading. We also thank Dr. Petcharat Trongtorsak of Allied Health Sciences, Burapha University for a very kind gift of forskolin, CCh, and nifedipine. We also thank Ms. Pattamaporn Ketkeaw and Mr. Chanin Nuekchob of the Faculty of Allied Health Sciences, Burapha University and Mr. Phongthon Kanjanasirirat of the Excellent Center for Drug Discovery (ECDD), Faculty of Science, Mahidol University for their excellent technical assistance.

Author contributions

TN designed and performed the experiments, analyzed and interpreted the results, and wrote and edited the manuscript. CS performed the experiments, analyzed the results, and wrote and edited the manuscript.


This study was funded by Burapha University through the National Research Council of Thailand (138/2560), and the Faculty of Allied Health Sciences, Burapha University (AHS06/2560) to N. Thongon.

Compliance with ethical standards

Conflict of interest

All authors declare that they have no competing interests.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

Not applicable.


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Copyright information

© The Physiological Society of Japan and Springer Japan KK, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Division of Physiology, Department of Biomedical Sciences, Faculty of Allied Health SciencesBurapha UniversityMuangThailand
  2. 2.Division of Anatomy, Department of Biomedical Sciences, Faculty of Allied Health SciencesBurapha UniversityMuangThailand

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