Adenosine Neuromodulation of Selectively Vulnerable CA1 Neurons
Adenosine is one of the most potent inhibitory modulators of neuronal activity in the hippocampus. This purine nucleoside acts as an endogenous anticonvulsant and its effects are mediated by specific, high-affinity, A1-type receptors that are concentrated in the selectively vulnerable CA1 area. The regional density of adenosine A1 receptors has been shown to be a critical factor controlling the strength of adenosine inhibition and the number of these receptors is reduced rapidly in CA1 following transient ischemia. The hypothesis is discussed that a postischemic attenuation of adenosine neuromodulation contributes to the destabilization of sensitive CA1 neurons.
KeywordsAdenosine Receptor Purine Nucleoside Transient Ischemia Neuronal Discharge Adenosine Receptor Antagonist
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