P2X7 Receptor-mediated Membrane Blebbing in Salivary Epithelial Cells.
10.4196/kjpp.2009.13.3.175
- Author:
Sung Min HWANG
1
;
Na Youn KOO
;
Se Young CHOI
;
Gae Sig CHUN
;
Joong Soo KIM
;
Kyungpyo PARK
Author Information
1. Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul 110-749, Korea. kppark@snu.ac.kr
- Publication Type:Original Article
- Keywords:
P2X7 receptor;
Membrane blebbing;
ROCKI;
Ca2+ influx
- MeSH:
Adenosine Triphosphate;
Blister;
Caspase 3;
Cell Death;
Epithelial Cells;
Membranes;
Phosphorylation;
Receptors, Purinergic P2X7;
Salivary Glands
- From:The Korean Journal of Physiology and Pharmacology
2009;13(3):175-179
- CountryRepublic of Korea
- Language:English
-
Abstract:
High concentrations of ATP induce membrane blebbing. However, the underlying mechanism involved in epithelial cells remains unclear. In this study, we investigated the role of the P2X7 receptor (P2X7R) in membrane blebbing using Par C5 cells. We stimulated the cells with 5 mM of ATP for 1~2 hrs and found the characteristics of membrane blebbing, a hallmark of apoptotic cell death. In addition, 500 micrometer Bz-ATP, a specific P2X7R agonist, induced membrane blebbing. However, 300 micrometer of Ox-ATP, a P2X7R antagonist, inhibited ATP-induced membrane blebbing, suggesting that ATP-induced membrane blebbing is mediated by P2X7R. We found that ATP-induced membrane blebbing was mediated by ROCK I activation and MLC phosphorylation, but not by caspase-3. Five mM of ATP evoked a biphasic [Ca2+]i response; a transient [Ca2+]i peak and sustained [Ca2+]i increase secondary to ATP-stimulated Ca2+ influx. These results suggest that P2X7R plays a role in membrane blebbing of the salivary gland epithelial cells.
