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Abstract

The psychostimulant caffeine promotes behavioral effects such as hyperlocomotion, anxiety, and disruption of sleep by blockade of adenosine receptors. The availability of extracellular adenosine depends on its release by transporters or by the extracellular ATP catabolism performed by the ecto-nucleotidase pathway. This study verified the effect of caffeine on NTPDase 1 (ATP diphosphohydrolase) and 5'-nucleotidase of synaptosomes from hippocampus and striatum of rats. Caffeine and theophylline tested in vitro were unable to modify nucleotide hydrolysis. Caffeine chronically administered in the drinking water at 0.3 g/L or 1 g/L for 14 days failed to affect nucleotide hydrolysis. However, acute administration of caffeine (30 mg/kg, i.p.) produced an enhancement of ATP (50%) and ADP (32%) hydrolysis in synaptosomes of hippocampus and striatum, respectively. This activation of ATP and ADP hydrolysis after acute treatment suggests a compensatory effect to increase adenosine levels and counteract the antagonist action of caffeine.

Caffeine inhibits gene conversion by displacing Rad51 from ssDNA

“…It is possible that caffeine leads to Rad51 eviction by stimulating Rad51 to hydrolyze ATP, analogous to results in other systems ( 70 , 71 ). We therefore used a rad51 Δ strain complemented by a centromere-containing plasmid with rad51-K191R expressed from its endogenous promoter to test for the involvement of ATP hydrolysis in dissociation of Rad51 filaments (Supplementary Figure S2A and B).…”

Concentration- and age-dependent effects of chronic caffeine on contextual fear conditioning in C57BL/6J mice

“…A preliminary dose analysis indicated that higher concentrations of caffeine were not well tolerated. Bottles were changed every 2-3 days as described previously (Boeck et al, 2009; da Silva et al, 2003). …”