Endogenous adenosine delays the onset of hypoxic depolarization in the rat hippocampus in vitro via an action at A1 receptors.
The effect of endogenous adenosine on the delay to hypoxic depolarization (HD) was examined utilizing in vitro slices of gerbil hippocampus. Adenosine receptor antagonists were used to block the actions of adenosine during hypoxia, and the delay to HD was measured in the CA1 region. Both a broad spectrum antagonist (theophylline) and an A1 receptor-specific antagonist (8-cyclopentyl-1,3-dimethylxanthine; CPT) shortened the delay to HD. These findings indicate that endogenous adenosine working through A1 receptors prolongs the delay to HD. This effect may contribute to the neuroprotective influence of adenosine and its analogs.
Department of Neurological Surgery, University of Virginia School of Medicine, Charlottesville 22908.
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Lowenkopf
D000241:Adenosine / Q000502:physiology*; D000818:Animals; D005071:Evoked Potentials / Q000502:physiology; D005849:Gerbillinae; D006624:Hippocampus / Q000187:drug effects*; D002534:Hypoxia, Brain / Q000503:physiopathology*; D066298:In Vitro Techniques; D058914:Purinergic Antagonists; D051381:Rats; D011983:Receptors, Purinergic / Q000187:drug effects*; D013806:Theophylline / Q000031:analogs & derivatives / Q000494:pharmacology
D058914:Purinergic Antagonists; D011983:Receptors, Purinergic; C053907:8-cyclopentyl-1,3-dimethylxanthine; D013806:Theophylline; D000241:Adenosine