Premium
Adenosine receptors in pancreatic ducts
Author(s) -
Hede Susanne Edeling,
Hansen Mette Rud,
Novak Ivana
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.5.a547
Subject(s) - adenosine , adenosine receptor , purinergic signalling , receptor , purinergic receptor , medicine , adenosine a2a receptor , endocrinology , adenosine a1 receptor , extracellular , stimulation , biology , adenosine a2b receptor , chemistry , microbiology and biotechnology , agonist
ATP is secreted from pancreatic acini and acts on pancreatic ducts to influence secretion. Pancreatic ducts express purinergic receptors of the P2 type, but little is known about adenosine receptors. Therefore the aim of this project was to determine the expression and function of adenosine receptors in pancreatic ducts. RT‐PCR analysis on rat pancreas and on isolated pancreatic ducts identified transcripts for the adenosine receptors A 1 , A 2A , A 2B and A 3 . This finding was confirmed by RT‐PCR on human ductal cell‐lines (PANC‐1, CFPAC, Capan‐1). In order to quantify the expression of adenosine receptors, real‐time PCR was performed. The expressions of the four transcripts were very low compared to Beta‐actin. Nevertheless, A 2A receptors were most abundant. Patch‐clamp experiments showed that about 50% of the native ducts examined responded to adenosine (1–100 μM). In these ducts the membrane potential depolarized by 10–40 mV and the whole‐cell conductance (G m ) increased by 30%. Lowering of extracellular Cl − resulted in additional depolarization of V m . In another set of experiments it was found that intracellular Ca 2+ was little affected by adenosine. Taken together, this study shows that the pancreatic ducts express functional adenosine receptors primarily of the A 2A type and adenosine stimulation results in opening of Cl − channels. Supported by the Lundbeck Foundation and the Danish Science Research Council.