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Updated: Jun 10, 2026

Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
β2-Adrenergic receptors and G-protein-coupled receptor kinase 2 in rabbit pleural mesothelium
Chiara Sironi1, Francesca Bodega, Marta Armilli
1Dipartimento di Fisiologia Umana, Università degli studi di Milano, Via Mangiagalli 32, 20133 Milan, Italy.
Abstract:
Former studies on net rate of liquid absorption from small Ringer or 1% albumin-Ringer hydrothoraces in rabbits indicated that Na+ transport and solute-coupled liquid absorption by mesothelium is increased by pleural liquid dilution, and stimulation of β2-adrenoreceptors (β2AR). In this research we tried to provide molecular evidence for β2AR in visceral and parietal mesothelium of rabbit pleura. Moreover, because prolonged stimulation of β2AR may lead to desensitization mediated by G-protein-coupled receptor kinase 2 (GRK2), we also checked whether GRK2 is expressed in pleural mesothelium. To this end we performed immunoblot assays on total protein extracts from scraped visceral and parietal mesothelium, and from cultured pleural mesothelial cells of rabbits. All three samples showed β2AR and GRK2 specific bands.
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