Multiple mechanisms of CB1 cannabinoid receptors regulation.

The Mauerberger Chair in Neuropharmacology, Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 69978, Israel.
Brain Research (Impact Factor: 2.83). 09/2003; 980(2):197-205. DOI: 10.1016/S0006-8993(03)02970-6
Source: PubMed

ABSTRACT Agonist-induced regulation of cannabinoid CB1 receptors was examined in HEK-293 cells transfected with CB1 receptors and in neuroblastoma N18TG2 cells that naturally express CB1 receptors. In HEK-293 cells, CB1 receptors internalization proceeded, in parallel, via clathrin-coated pits and caveolae. Simultaneous disruption of both pathways induced compensatory endocytic mechanism(s). In N18TG2 cells, endocytosis was not mediated by caveolae-like membrane domains. Heterologous, opioid-induced, downregulation of CB1 receptors was evident in HEK-293 but not N18TG2 cells. The data demonstrate the existence of multiple pathways of CB1 receptors regulation.

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