ACELL August 46/2
نویسندگان
چکیده
Luo, Xiang, Weizhong Zheng, Ming Yan, Min Goo Lee, and Shmuel Muallem. Multiple functional P2X and P2Y receptors in the luminal and basolateral membranes of pancreatic duct cells. Am. J. Physiol. 277 (Cell Physiol. 46): C205–C215, 1999.—Purinergic receptors in the basolateral and luminal membranes of the pancreatic duct can act by a feedback mechanism to coordinate transport activity in the two membranes during ductal secretion. The goal of the present work was to identify and localize the functional P2 receptors (P2R) in the rat pancreatic duct. The lack of selective agonists and/or antagonists for any of the cloned P2R dictated the use of molecular and functional approaches to the characterization of ductal P2R. For the molecular studies, RNA was prepared from microdissected pancreatic intralobular ducts and was shown to be free of mRNA for amylase and endothelial nitric oxide synthase (markers for acinar and endothelial cells, respectively). A new procedure is described to obtain an enriched preparation of single duct cells suitable for electrophysiological studies. Localization of P2R was achieved by testing the effect of various P2R agonists on intracellular Ca21 concentration ([Ca]i) of microperfused intralobular ducts. RT-PCR analysis suggested the expression of six subtypes of P2R in the pancreatic duct: three P2YR and three P2XR. Activation of Cl2 current by various nucleotides and coupling of the receptors activated by these nucleotides to G proteins confirmed the expression of multiple P2R in duct cells. Measurement of [Ca]i in microperfused intralobular ducts suggested the expression of P2X1R, P2X4R, probably P2X7R, and as yet unidentified P2YR, possibly P2Y1R, in the basolateral membrane. Expression of P2Y2R, P2Y4R, and P2X7R was found in the luminal membrane. The unprecedented expression of such a variety of P2R in one cell type, many capable of activating Cl2 channels, suggests that these receptors may have an important role in pancreatic duct cell function.
منابع مشابه
ACELL August 46/2
JOHN M. PARK,1 ROSALYN M. ADAM,1 CRAIG A. PETERS,1 PAUL D. GUTHRIE,1 ZIJIE SUN,2 MICHAEL KLAGSBRUN,3 AND MICHAEL R. FREEMAN3 1Urologic Laboratory, Department of Urology, 3Laboratory for Surgical Research, Children’s Hospital, and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115; and 2Departments of Surgery and Genetics, Stanford University School of Medicine, Stanford,...
متن کاملACELL November 46/5
ESTHER TITOS,1 NAN CHIANG,2 CHARLES N. SERHAN,2 MARIO ROMANO,3 JOAN GAYA,4 GLORIA PUEYO,5 AND JOAN CLÀRIA1 1DNA Unit and 4Hormonal Laboratory, Institut d’Investigacions Biomèdiques August Pi i Sunyer, Hospital Clı́nic and 5Quı́mica Farmacéutica Bayer (Consumer Care Division), Barcelona 08036, Spain; 2Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Periop...
متن کاملACELL October 46/4
NABENDU S. CHATTERJEE,1 CHANDIRA K. KUMAR,1 ALVARO ORTIZ,1 STANLEY A. RUBIN,2 AND HAMID M. SAID1 1Medical Research Service, Veterans Affairs Medical Center, Long Beach 90822, and Department of Medicine and Physiology/Biophysics, University of California School of Medicine, Irvine 92697; and 2Veterans Affairs West Los Angeles, Los Angeles 90073, and Department of Medicine, University of Californ...
متن کاملACELL August 46/2
Tonkonogi, M., and K. Sahlin. Actively phosphorylating mitochondria are more resistant to lactic acidosis than inactive mitochondria. Am. J. Physiol. 277 (Cell Physiol. 46): C288–C293, 1999.—Oxidative phosphorylation of isolated rat skeletal muscle mitochondria after exposure to lactic acidosis in either phosphorylating or nonphosphorylating states has been evaluated. Mitochondrial respiration ...
متن کاملACELL August 46/2
Golovina, Vera A. Cell proliferation is associated with enhanced capacitative Ca21 entry in human arterial myocytes. Am. J. Physiol. 277 (Cell Physiol. 46): C343–C349, 1999.—Depletion of Ca21 stores in the sarcoplasmic reticulum (SR) activates extracellular Ca21 influx via capacitative Ca21 entry (CCE). Here, CCE levels in proliferating and growth-arrested human pulmonary artery smooth muscle c...
متن کامل