INCREASE ON CDK5 ACTIVITY IN STRIATAL SYNAPTOSOMES AFTER SENSITIZATION TO AMPHETAMINE IN A NOVEL ENVIRONMENT IN PERIADOLECENTS RATS

MLEWSKI, E.C.; ARIAS, C.; PAGLINI, M.G.

Huerta Grande

Congreso; Sociedad Argentina de Neurociencias; 2009

Sociedad Argentina de Neurociencias

The development of sensitization to the locomotor effects of psychostimulant is strongly influenced by the environmental context in which a stimulant drug is administered. This particularity represents a valuable tool to analyze neurochemical changes specifically associated the development of sensitization. Recent data from our laboratory suggest that the p35/cdk5 complex is involved in the development of behavioral sensitization induced by d-amphetamine (amph) in the periadolecent rat. The present study was designed to analyze whether: a) an acute administration of amph produces sensitization in adolescent rats, b) this effect is modulated by the novelty of the context, and c) changes in activity of Cdk5 are associated with the development of sensitization. Periadolescent rats were given 0 or 4 mg/kg amph in a novel environment or in the homecage. After one day of withdrawal subjects were given vehicle or 2mg/kg amph in the same context where received the first administration of the drug. Locomotor activity and the expression of p35 and Cdk5 activity in synaptosomes of dorsal striatum test were analyzed. Behavioral sensitization was only observed in the novel condition. This sensitization was specifically accompanied with an augmentation of the expression of p35 and the activity of cdk5 in dorsal striatum. These results support the hypothesis which postulates that the p35/cdk5 complex plays a role in the sensitization to the stimulant locomotor effects of amph.