Table 3.

Role of purinoreceptors in experimental models and patients with Alzheimer's disease (AD) and Parkinson's disease (PD).

R Sample	P2X7 receptor	A2A receptor	Reference
Transgenic mouse model of AD (brain slices)	Upregulated	—	[169]
Microglia from AD patients Human microglia treated with amyloid-beta peptide in vitro Rat hippocampus after amyloid-beta peptide injection	Upregulated	—	[170]
Transgenic mouse model of AD	Inhibition of P2X7R decreased the number of hippocampal amyloid plaques	—	[171]
Human macrophages and microglia preactivated with amyloid-beta peptide	P2X7R stimulation enhanced secretion of proinflammatory cytokines	—	[172, 173]
Rats injected with 6-OHDA	—	Inhibition of A2AR improved motor performance and cognition	[174]
Rats injected with haloperidol (DA antagonist)	—	Inhibition of A2AR reversed locomotor suppression and tremulous jaw movements	[174, 175]

Alzheimer's disease (AD), P2X7 receptors (P2X7R), adenosine A2A receptor (A2AR), 6-hydroxydopamine (6-OHDA), and dopamine (DA).