The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

ludc web

Joao Duarte

Principal investigator

ludc web

Modification of adenosine A1 and A2A receptor density in the hippocampus of streptozotocin-induced diabetic rats

Author

  • João M N Duarte
  • Catarina R Oliveira
  • António F Ambrósio
  • Rodrigo A Cunha

Summary, in English

Adenosine A(1) and A(2A) receptors are neuromodulatory systems that can control mnemonic behavior, which is modified by diabetes. Since the density of these adenosine receptors can change upon chronic noxious brain conditions, we now tested if the density of A(1) and A(2A) receptors was modified in the hippocampus of streptozotocin-induced diabetic rats. The binding density of the selective A(1) receptor antagonist, (3)H-DPCPX, was decreased by 36% in total hippocampal membranes 7 days after induction of diabetes and this down-regulation was maintained after 30 and 90 days, which was also confirmed by Western blot analysis of A(1) receptor immunoreactivity. In contrast, the binding density of the selective A(2A) receptor antagonist, (3)H-SCH 58261, was enhanced by 83% in total hippocampal membranes 7 days after induction of diabetes and this up-regulation persisted after 30 and 90 days. These results show that the balance between inhibitory A(1) and facilitatory A(2A) adenosine receptors is modified in the hippocampus of streptozotocin-induced diabetic rats. Thus, the most abundant A(1) receptors are down-regulated and there is an up-regulation of A(2A) receptors, suggesting a gain of function of hippocampal A(2A) receptors compared to A(1) receptors in diabetes, as has been observed in other chronic noxious brain conditions where A(2A) receptor blockade affords robust neuroprotection.

Publishing year

2006-01

Language

English

Pages

144-150

Publication/Series

Neurochemistry International

Volume

48

Issue

2

Document type

Journal article

Publisher

Elsevier

Topic

  • Neurosciences
  • Endocrinology and Diabetes

Keywords

  • Animals
  • Blotting, Western
  • Diabetes Mellitus, Experimental/metabolism
  • Hippocampus/metabolism
  • Male
  • Rats
  • Rats, Wistar
  • Receptor, Adenosine A1/metabolism
  • Receptor, Adenosine A2A/metabolism
  • Streptozocin

Status

Published

ISBN/ISSN/Other

  • ISSN: 0197-0186