Rabbit pancreatic acini express cftr as a camp-activated chloride
efflux pathway.
Kopelman, Hinda, Emanuela Ferretti, Claude Gauthier, Paul R Goodyer.
Divisions of Gastroenterology/Nutrition and Nephrology, Department
of Pediatrics, McGill University-Montreal Children's Hospital
Research Institute, Montreal, Canada
APStracts 2:0138C, 1995.
CFTR is responsible for cAMP-activated chloride (Cl) transport in
epithelial cells. Isolated rabbit pancreatic acini possess a cAMP
-activated Cl efflux mechanism distinct from zymogen granule
secretion. To determine whether CFTR is expressed in acini, we used
PCR to amplify a 480 base-pair (bp) sequence from reverse-transcribed
rabbit acinar RNA. The PCR product was consistent with a 480 bp band
amplified in T84 cells and its sequence was >90% homologous to
human CFTR. CFTR antibody M3A7 recognized a 180Kd and a 160Kd protein
from acinar membranes and in CHO cells transfected with CFTR. To
determine if CFTR was responsible for the cAMP-activated Cl efflux
previously demonstrated in pancreatic acini, we incubated acinar
cells for 20 hours with 1.75[mu]M CFTR antisense or sense oligodnt.
Cl efflux in response to 8BrcAMP and phorbol ester, but not in
response to calcium ionophore, was selectively inhibited by CFTR
antisense oligodnt. Antisense oligodnt did not inhibit acinar amylase
secretion. These findings indicate that isolated pancreatic acini can
be used for future studies of CFTR expression and function.
Received 18 August 1994; accepted in final form 23 February 1995.
APS Manuscript Number C494-4.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 21 March 1995.