Effect of Caffeine on UTP-induced Ca2+ Mobilization and Mucin Secretion in Human Middle Ear Epithelial Cells.
- Author:
Jae Young CHOI
1
;
Sung Huhn KIM
;
Sang Ho JUNG
;
Eun Jin SON
;
Hun Yi PARK
;
Joong Wook SHIN
;
Joo Heon YOON
Author Information
1. Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Korea. jhyoon@yumc.yonsei.ac.kr
- Publication Type:Original Article
- Keywords:
Mucin;
Caffeine;
Calcium
- MeSH:
Adenosine;
Adenosine Triphosphate;
Caffeine*;
Calcium;
Ear, Middle*;
Epithelial Cells*;
Humans*;
Immunoblotting;
Inositol;
Mucins*;
Otitis Media;
Perfusion;
Purinergic Agonists;
Uridine Triphosphate
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2006;49(3):263-268
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND AND OBJECTIVES: Puringeric receptors and their agonists like uridine-5-triphosphate (UTP) and adenosine triphosphate (ATP), regulate mucin secretion in middle ear epithelial cells. In the present study, we examined the effects of purinergic agonists on Ca2+ influx ([Ca2+]i ) in normal human middle ear epithelial (NHMEE) cells. We also examined the effect of caffeine, an inositol 1, 4, 5-triphosphate (IP3) inhibitor, on UTP induced [Ca2+]i and mucin secretion in NHMEE cells. MATERIALS AND METHOD: NHMEE cells were stimulated with various purinergic agonists, such as UTP, and [Ca2+]i was measured using a miniature double perfusion chamber. UTP-induced mucin secretion was quantitated by immunoblotting assay. RESULTS: The determined order of purinergic agonist potency with respect to [Ca2+]i was ATP=UTP>2-MeSATP>ADP>> adenosine. UTP-induced mucin secretion was inhibited when the intracellular Ca2+ was removed with 2-bis (2-aminophenoxy)ethane-N, N, N', N'-tetraacetic acid-acetoxymethyl ester. Caffeine suppressed UTP-induced [Ca2+]i, and but inhibited UTPinduced and constitutional mucin secretion. CONCLUSION: Our results suggest that caffeine may have a therapeutic effect in mucoid otitis media by suppressing mucin secretion.
