Varenicline is a
drug used for
smoking addiction cessation
treatment and acts as a partial agonist of nicotinic
cholinergic receptors. Recent
clinical trial data support use of
varenicline for
treatment of conditions/addictions that are not related to
smoking cessation. Considering the importance of this issue and the need for new studies on its effects, especially on
behavior, more studies using
animal models are necessary. Thus, the aim of this study was to evaluate the effects of prolonged exposure to
varenicline in
anxiety-like
behavior and
memory, as well as in cerebral
neurochemistry of
rats.
Male rats received three different doses of
varenicline 0.03 (
therapeutic dose for
humans), 0.1 and 0.3?mg/kg orally (gavage) for 30?days.
Animal behavior was analyzed through open field,
elevated plus maze,
light/dark box,
social interaction, Barnes maze and novel object recognition tests.
Neurotransmitter levels and their metabolites in different
brain structures (
hippocampus, striatum and
frontal cortex) were measured. Results showed that prolonged exposure of
rats to
varenicline 1) did not interfere in
motor activity, but caused an anxiogenic effect on
elevated plus maze,
light/dark box and
social interaction testes; 2) did not alter
memory; and 3) promoted alterations on serotoninergic system in the striatum and
frontal cortex. In conclusion, compilation of the data indicates that prolonged exposure of
rats to
varenicline promoted anxiogenic effects and alteration in serotonergic system, which corroborated behavioral findings.