22 research outputs found
Effects of the cannabinoid CB1 receptor antagonist rimonabant on distinct measures of impulsive behavior in rats
Rationale Pathological impulsivity is a prominent feature in several psychiatric disorders, but detailed understanding of the specific
neuronal processes underlying impulsive behavior is as yet lacking.
Objectives As recent findings have suggested involvement of the brain cannabinoid system in impulsivity, the present study aimed at further
elucidating the role of cannabinoid CB1 receptor activation in distinct measures of impulsive behavior.
Materials and methods The effects of the selective cannabinoid CB1 receptor antagonist, rimonabant (SR141716A) and agonist WIN55,212-2 were tested in various measures of impulsive behavior,
namely, inhibitory control in a five-choice serial reaction time task (5-CSRTT), impulsive choice in a delayed reward paradigm,
and response inhibition in a stop-signal paradigm.
Results In the 5-CSRTT, SR141716A dose-dependently improved inhibitory control by decreasing the number of premature responses. Furthermore,
SR141716A slightly improved attentional function, increased correct response latency, but did not affect other parameters.
The CB1 receptor agonist WIN55,212-2 did not change inhibitory control in the 5-CSRTT and only increased response latencies and errors
of omissions. Coadministration of WIN55,212-2 prevented the effects of SR141716A on inhibitory control in the 5-CSRTT. Impulsive
choice and response inhibition were not affected by SR141716A at any dose, whereas WIN55,212-2 slightly impaired response
inhibition but did not change impulsive choice.
Conclusions The present data suggest that particularly the endocannabinoid system seems involved in some measures of impulsivity and provides
further evidence for the existence of distinct forms of impulsivity that can be pharmacologically dissociated