Block of purinergic P2X(7) receptor is neuroprotective in an animal model of Alzheimer's disease.

Pharmacological antagonism of the ionotropic purinergic P2X7R has been studied for effects on inflammatory reactivity and neuronal viability in amyloid-beta1-42-injected rat hippocampus. Amyloid-beta1-42-injected brains (7-day postinjection) demonstrated marked increases in P2X7R expression, gliosis, leakiness of blood-brain barrier and loss of hippocampal neurons. The P2X7R antagonist, brilliant blue G reduced levels of purinergic receptor expression, attenuated gliosis, diminished leakiness of blood-brain barrier and was neuroprotective in peptide-injected brain. Brilliant blue G also demonstrated neuroprotection and antagonism against inflammatory responses induced by the P2X7R agonist, 2',3'-(benzoyl-4-benzoyl)-ATP. The findings constitute the first report that pharmacological inhibition of P2X7R, possibly by acting to inhibit inflammatory reactivity, confers neuroprotection in an animal model of Alzheimer's disease brain.