INVESTIGADORES
CANCELA Liliana Marina
artículos
Título:
A dopaminergic mechanism is involved in the anxiogenic-like response induced by chronic amphetamine treatment: a behavioral and neurochemical study
Autor/es:
L.M. CANCELA*, A.M. BASSO, I.D. MARTIJENA, N.R. CAPRILES1, V.A. MOLINA
Revista:
BRAIN RESEARCH
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2001 vol. 909 p. 179 - 186
ISSN:
0006-8993
Resumen:
The purpose of this study was to examine the influence of chronic d-amphetamine (AMPH) treatment (2 mg/kg i.p., for 9 consecutive
days) on behavioral and neurochemical responses to a subsequent exposure 4 days after the last AMPH injection to the elevated
plus-maze (EPM), as well as to determine the involvement of a dopaminergic mechanism in that influence. Results showed that chronic
AMPH treatment induced an anxiogenic-like response when animals were evaluated in the EPM test. Pretreatment with either
haloperidol (HAL, 1 mg/kg i.p., 20 min prior to each injection) or SCH-23390 (0.1 mg/kg i.p., 10 min prior to each injection) completely
abolished the chronic AMPH-induced anxiogenic-like effect displayed in the EPM test. However, sulpiride pretreatment (60 mg/kg i.p.,
10 min prior to each AMPH injection) did not modify such effect. In addition, rats treated with AMPH and subsequently exposed to the
EPM, showed a decrease in the maximal GABA-stimulated chloride uptake in cortical microsacs. HAL pretreatment restored the maximal
chloride uptake induced by chronic AMPH. Altogether, these results suggest that: (1) previous exposure to chronic AMPH treatment
induces an increased emotional response following a conflict situation, (2) dopamine D receptors are mainly involved in chronic 1
days) on behavioral and neurochemical responses to a subsequent exposure 4 days after the last AMPH injection to the elevated
plus-maze (EPM), as well as to determine the involvement of a dopaminergic mechanism in that influence. Results showed that chronic
AMPH treatment induced an anxiogenic-like response when animals were evaluated in the EPM test. Pretreatment with either
haloperidol (HAL, 1 mg/kg i.p., 20 min prior to each injection) or SCH-23390 (0.1 mg/kg i.p., 10 min prior to each injection) completely
abolished the chronic AMPH-induced anxiogenic-like effect displayed in the EPM test. However, sulpiride pretreatment (60 mg/kg i.p.,
10 min prior to each AMPH injection) did not modify such effect. In addition, rats treated with AMPH and subsequently exposed to the
EPM, showed a decrease in the maximal GABA-stimulated chloride uptake in cortical microsacs. HAL pretreatment restored the maximal
chloride uptake induced by chronic AMPH. Altogether, these results suggest that: (1) previous exposure to chronic AMPH treatment
induces an increased emotional response following a conflict situation, (2) dopamine D receptors are mainly involved in chronic 1
d-amphetamine (AMPH) treatment (2 mg/kg i.p., for 9 consecutive
days) on behavioral and neurochemical responses to a subsequent exposure 4 days after the last AMPH injection to the elevated
plus-maze (EPM), as well as to determine the involvement of a dopaminergic mechanism in that influence. Results showed that chronic
AMPH treatment induced an anxiogenic-like response when animals were evaluated in the EPM test. Pretreatment with either
haloperidol (HAL, 1 mg/kg i.p., 20 min prior to each injection) or SCH-23390 (0.1 mg/kg i.p., 10 min prior to each injection) completely
abolished the chronic AMPH-induced anxiogenic-like effect displayed in the EPM test. However, sulpiride pretreatment (60 mg/kg i.p.,
10 min prior to each AMPH injection) did not modify such effect. In addition, rats treated with AMPH and subsequently exposed to the
EPM, showed a decrease in the maximal GABA-stimulated chloride uptake in cortical microsacs. HAL pretreatment restored the maximal
chloride uptake induced by chronic AMPH. Altogether, these results suggest that: (1) previous exposure to chronic AMPH treatment
induces an increased emotional response following a conflict situation, (2) dopamine D receptors are mainly involved in chronic 11
AMPH-induced changes in the behavior displayed in EPM test, and (3) an interaction between GABAergic and dopaminergic
mechanisms may be implicated in neurochemical and behavioral changes induced by chronic AMPH treatment. Ó 2001 Published by
Elsevier Science B.V.
Elsevier Science B.V.
Ó 2001 Published by
Elsevier Science B.V.