Differential effects of endocannabinoids on [(3)H]-GABA uptake in the rat globus pallidus.
In the globus pallidus, cannabinoid CB(1) receptors are localized pre-synaptically on GABAergic neurons. We assessed the influence of the endocannabinoids, anandamide, 2-arachidonoyl-glycerol (2-AG) and noladin ether, on the uptake of [(3)H]-GABA in pallidal slices from rat. Both 2-AG and noladin ether increased [(3)H]-GABA uptake (by 40.8 +/- 8.0% and 38.4 +/- 12.5%). The effect of 2-AG was blocked by the cannabinoid CB(1) receptor antagonist AM 251. In contrast, neither anandamide nor the agonist WIN 55,212-2 had an effect on [(3)H]-GABA uptake. Different roles might be played by different endocannabinoids, both physiologically and in basal ganglia disorders, such as Parkinson's disease.
Venderova
Katerina
K
Toronto Western Research Institute, Toronto Western Hospital, 399 Bathurst Street, MC 11-419, Toronto, Ontario, Canada M5T 258. venderova@yahoo.com
Brown
Timothy M
TM
Brotchie
Jonathan M
JM
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D001667:Binding, Competitive / Q000187:drug effects; D063385:Cannabinoid Receptor Modulators / Q000494:pharmacology*; D063388:Endocannabinoids; D005917:Globus Pallidus / Q000187:drug effects* / Q000378:metabolism*; D005989:Glycerides / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D010880:Piperidines / Q000494:pharmacology; D053284:Polyunsaturated Alkamides; D011720:Pyrazoles / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D043884:Receptor, Cannabinoid, CB1 / Q000037:antagonists & inhibitors; D014316:Tritium; D005680:gamma-Aminobutyric Acid / Q000493:pharmacokinetics*
D001095:Arachidonic Acids; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D005989:Glycerides; D010880:Piperidines; D053284:Polyunsaturated Alkamides; D011720:Pyrazoles; D043884:Receptor, Cannabinoid, CB1; C424442:noladin ether; D014316:Tritium; C103505:AM 251; D005680:gamma-Aminobutyric Acid; C094503:glyceryl 2-arachidonate; C078814:anandamide