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An. R. Acad. Nac. Farm., 2008, 74: 387-408

Sesiones

Fine tuning neuromodulation by adenosine
and neuroprotection

Recibido el 14 de febrero de 2008

RIBEIRO, J. A. *
Institute of Pharmacology and Neurosciences.
Faculty of Medicine and Unit of Neurosciences,

Institute of Molecular Medicine.
University of Lisboa.

ABSTRACT

Adenosine fine tuning neuromodulation is a very subtle change, similar to what
e.g., a pianist does, modulating a sound through insertion of another sound;
so, modifying the characteristics of the previous sound. This is what adenosine
does to modulate neurotransmitter actions. Adenosine neuromodulation is operated
through high affinity inhibitory A1 and excitatory A2A receptors. These receptors
have the particularity of interacting with receptors for other neurotransmitters and
neuromodulators as well as with adenosine transport systems. This modulation is
involved in neuroprotection namely via adenosine A1 receptors in neurotoxicity
during hypoxia, reactive oxygen species insults either inhibiting NMDA receptors
or as part of interleukin-6 neuroprotecive effects. On the other hand A2A receptors
mainly trigger the action of several promoters of neuroprotection, e.g., BDNF and
GDNF.

Key words: Adenosine receptors.—Neuromodulation.—Neuroprotection.

* Contact adress:
Professor Joaquim A. Ribeiro.
Institute of Pharmacology and Neurosciences, Faculty of Medicine and Unit of
Neurosciences, Institute of Molecular Medicine, University of Lisboa, 1649-028 Lisboa,
Portugal.
Email: jaribeiro@fm.ul.pt

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