Please use this identifier to cite or link to this item: http://hdl.handle.net/10316/4719
Title: Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats
Authors: Rodrigues, Ricardo J. 
Canas, Paula M. 
Lopes, Luísa V. 
Oliveira, Catarina R. 
Cunha, Rodrigo A. 
Keywords: Adenosine; Acetylcholine; Nerve terminals; Localization; Density
Issue Date: 1-Sep-2008
Citation: Neurobiology of Aging. In Press, Corrected Proof:
Abstract: Adenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs. Since A2AR antagonists attenuate memory deficits in aged animals and memory deficits might involve a decreased cholinergic function, we investigated how aging affects the density and function of adenosine receptors in rat hippocampal cholinergic terminals. In young adult (2 months) rats, 64 and 36% of cholinergic terminals (immunopositive for vesicular ACh transporters) possessed A1Rs and A2ARs, respectively. In aged (24 months) rats, the percentage of cholinergic terminals with A1Rs was preserved, whereas that with A2ARs was larger (49%). In young adults adenosine only tonically inhibited ACh release through A1Rs, whereas in aged rats there was a greater A1R-mediated inhibition and a simultaneous A2AR-mediated facilitation of ACh release. Thus, the enhanced A2AR density and facilitation compensates for the greater tonic A1R modulation, preserving the global adenosine modulation of ACh release in aged rats. Furthermore, since A2AR antagonists inhibit ACh release, the beneficial effects of A2AR antagonists on memory in aged rats might not result from ACh release modulation.
URI: http://hdl.handle.net/10316/4719
Rights: openAccess
Appears in Collections:FMUC Medicina - Artigos em Revistas Internacionais

Files in This Item:
File Description SizeFormat
file0353036cfa2c44f997f3dc74b9522269.pdf289.13 kBAdobe PDFView/Open
Show full item record

Page view(s) 50

386
checked on Dec 3, 2019

Download(s)

110
checked on Dec 3, 2019

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.