GM1 ganglioside facilitates the rewarding properties of cocaine in rats

VALDOMERO A.; VELAZQUEZ EE.; MORA M.; CUADRA GR.; ORSINGHER OA.

Córdoba

Congreso; XXXVIII Reunión Científica de la Sociedad Argentina de Farmacología Experimental; 2006

Gangliosides, which are natural components of neuronal membranes, seem to play a relevant rol in neuronal plasticity phenomena. Several lines of evidence have demonstrated that pretreatment with gangliosides accelerates plastic neuronal changes induced by different pharmacological treatments. Using an unbiased place conditioning procedure (CPP paradigm), we have analyzed the influence of GM1 ganglioside pretreatment on cocaine induced conditioned rewarding effects. Previous reports from our Lab have demonstrated that four conditioning sessions employing 10mg/kg i.p. of cocaine are necessary to induce conditioning effects in control rats. Pretreatment with GM1 (30 mg/kg i.p.) two hours before cocaine administration (5 mg/kg) elicited conditioned place preference following four conditioning sessions. Furthermore, GM1 co-administration leads to place conditioning using 10 mg/kg of cocaine after two and three conditioning sessions, whereas no effect was found after 4 sessions. Thus, GM1 co-administration enhanced the rewarding properties of cocaine since it decreased the effective dose of cocaine necessary to induce conditioned place preference as well as the number of conditioning sessions. Since central dopaminergic system is critically involved in reward mechanism, these preliminary results suggest that GM1 ganglioside plays an important role in the events related to dopaminergic plasticity