Accumulation of N-arachidonoylethanolamine (anandamide) into cerebellar granule cells occurs via facilitated diffusion. J Neurochem 1997 Aug;69(2):631-8
Date
08/01/1997Pubmed ID
9231721DOI
10.1046/j.1471-4159.1997.69020631.xScopus ID
2-s2.0-0030852614 (requires institutional sign-in at Scopus site) 320 CitationsAbstract
N-Arachidonoylethanolamine (anandamide, AEA) is a putative endogenous ligand of the cannabinoid receptor. Intact cerebellar granule neurons in primary culture rapidly accumulate AEA. [3H]AEA accumulation by cerebellar granule cells is dependent on incubation time (t(1/2) of 2.6 +/- 0.8 min at 37 degrees C) and temperature. The accumulation of AEA is saturable and has an apparent Km of 41 +/- 15 microM and a Vmax of 0.61 +/- 0.04 nmol/min/10(6) cells. [3H]AEA accumulation by cerebellar granule cells is significantly reduced by 200 microM phloretin (57.4 +/- 4% of control) in a noncompetitive manner. [3H]AEA accumulation is not inhibited by either ouabain or removal of extracellular sodium. [3H]AEA accumulation is fairly selective for AEA among other naturally occurring N-acylethanolamines; only N-oleoylethanolamine significantly inhibited [3H]AEA accumulation at a concentration of 10 microM. The ethanolamides of palmitic acid and linolenic acid were inactive at 10 microM. N-Arachidonoylbenzylamine and N-arachidonoylpropylamine, but not arachidonic acid, 15-hydroxy-AEA, or 12-hydroxy-AEA, compete for AEA accumulation. When cells are preloaded with [3H]AEA, temperature-dependent efflux occurs with a half-life of 1.9 +/- 1.0 min. Phloretin does not inhibit [3H]AEA efflux from cells. These results suggest that AEA is accumulated by cerebellar granule cells by a protein-mediated transport process that has the characteristics of facilitated diffusion.
Author List
Hillard CJ, Edgemond WS, Jarrahian A, Campbell WBAuthors
William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinCecilia J. Hillard PhD Associate Dean, Center Director, Professor in the Pharmacology and Toxicology department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AnimalsArachidonic Acids
Binding, Competitive
Biological Transport
Cannabinoids
Carrier Proteins
Cells, Cultured
Cerebellum
Diffusion
Endocannabinoids
Enzyme Inhibitors
Female
Kinetics
Male
Ouabain
Phloretin
Polyunsaturated Alkamides
Rats
Receptors, Cannabinoid
Receptors, Drug
Sodium-Potassium-Exchanging ATPase
Temperature