Effects of caffeine on striatal neurotransmission: focus on cannabinoid CB1 receptors.
Caffeine is the most commonly self-administered psychoactive substance worldwide. At usual doses, the effects of caffeine on vigilance, attention, mood and arousal largely depend on the modulation of central adenosine receptors. The present review article describes the action of caffeine within the striatum, to provide a possible molecular mechanism at the basis of the psychomotor and reinforcing properties of this pharmacological agent. The striatum is in fact a subcortical area involved in sensorimotor, cognitive, and emotional processes, and recent experimental findings showed that chronic caffeine consumption enhances the sensitivity of striatal GABAergic synapses to the stimulation of cannabinoid CB1 receptors. The endocannabinoid system is involved in the psychoactive effects of many compounds, and adenosine A2A receptors (the main receptor target of caffeine) elicit a permissive effect towards CB1 receptors, thus suggesting that A2A-CB1 receptor interaction plays a major role in the generation and maintenance of caffeine reinforcing behavior. Aim of this review is to describe the effects of caffeine on striatal neurotransmission with special reference to the modulation of the endocannabinoid system.
Rossi
Silvia
S
Clinica Neurologica, Dipartimento di Neuroscienze, Universitá Tor Vergata, Rome, Italy.
De Chiara
Valentina
V
Musella
Alessandra
A
Mataluni
Giorgia
G
Sacchetti
Lucia
L
Siracusano
Alberto
A
Bernardi
Giorgio
G
Usiello
Alessandro
A
Centonze
Diego
D
D000818:Animals; D001519:Behavior / Q000187:drug effects; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003342:Corpus Striatum / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D011597:Psychomotor Performance / Q000187:drug effects; D043705:Receptor, Adenosine A2A / Q000187:drug effects / Q000502:physiology; D043884:Receptor, Cannabinoid, CB1 / Q000187:drug effects* / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*
D000697:Central Nervous System Stimulants; D043705:Receptor, Adenosine A2A; D043884:Receptor, Cannabinoid, CB1; D002110:Caffeine