Regulation of extracellular adenosine levels in the striatum of aging rats

doi:10.1016/0006-8993(95)00471-2

Brain Research

Volume 684, Issue 1, 26 June 1995, Pages 103-106

https://doi.org/10.1016/0006-8993(95)00471-2 Get rights and content

Abstract

Extracellular adenosine concentrations, evaluated by microdialysis in the striatum of young and aged rats, were 66.8 ± 0.7 and 71.6 ± 1.0 nM, respectively. The adenosine deaminase inhibitor EHNA (100 μM) increased the extracellular adenosine levels in young rats only. The adenosine kinase inhibitor iodotubercidin (10 μM) brought about the same increase in young and aged rats. In aged rats the resting adenosine outflow was reduced by theN-methyl-D-aspartate (NMDA) receptor antagonist D-(−)-2-amino-7-phophonoheptanoic acid (D-AP7) (1 mM). It is concluded that extracellular levels of adenosine in the striatum are not affected by age, irrespective of the differences in adenosine deaminase activity and that the release of excitatory amino acids is responsible for much of resting adenosine outflow in aged but not in young rats.

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Regulation of extracellular adenosine levels in the striatum of aging rats

Abstract

Brain Res.

Neurosci. Lett.

Mech. Ageing Dev.

Neurobiol. Aging

Exp. Gerontol.

Brain Res. Bull.

Brain Res.

Eur. J. Pharmacol.

Eur. J. Pharmacol.

Pharmacol. Biochem. Behav.