Cellular and molecular neurobiology
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Cell. Mol. Neurobiol. · Apr 2003
Comparative StudyIntrathecal adenosine A1 receptor agonist attenuates hyperalgesia without inhibiting spinal glutamate release in the rat.
The analgesia effects of intrathecal adenosine A1 receptor agonist, R-PIA, on the hyperalgesia and CSF-glutamate release after formalin injection into the rat paw were evaluated. R-PIA significantly and dose-dependently attenuated increases in flinching behavior, and this attenuating effect was reversed by the adenosine A1 receptor antagonist, aminophylline. ⋯ The increase in CSF-glutamate release evoked by formalin stimulation was inhibited by morphine but not by either R-PIA or MK-801. These findings suggest that the intrathecal adenosine A1 receptor agonist provokes analgesic effect via the postsynaptic action independent of an effect upon spinal glutamate release.