Baclofen modifies nicotine behavioural responses, but not motivational manifestations of nicotine withdrawal in mice

ASO E., MALDONADO R. AND BALERIO G.

Córdoba, Argentina

Congreso; XXXVIII Reunión Anual de Comunicaciones Científicas; 2006

Sociedad Argentina de Farmacología Experimental

BACLOFEN MODIFIES NICOTINE BEHAVIOURAL RESPONSES, BUT NOT MOTIVATIONAL MANIFESTATIONS OF NICOTINE WITHDRAWAL IN MICE Aso E1, Maldonado Rl and Balerio G2,3 1Laboratorio de Neurofarmacología, Universitat Pompeu Fabra, Barcelona, España; 2ININFA (CONICET) y 3Cát. de Farmacología (FFYB, UBA).  Junín 956, 5º. Bs As-Argentina. E-mail: gbalerio@ffyb.uba.ar.   Nicotine (NIC) is one of the active components of tobacco and play a major role in tobacco addiction. Previous studies in rodents have shown that NIC modifies locomotion, anxiety, nociception learning and memory. Repeated nicotine administration produces several behavioural responses in animals closely related to its addictive properties, such as reinforcing effects and physical dependence.  The aim of the present study was to evaluate the possible role of GABAB receptor in responses induced by acute and repeated NIC administration by using CD1 mice. Acute NIC (3 mg/kg, sc) administration decreased locomotor activity and induced antinociceptive responses in the tail-immersion and the hot-plate test. Baclofen (BAC, GABAB receptor agonist) (2 mg/kg, i.p.) increased (p<0.05) the hypolocomotion induced by NIC and decreased (p<0.05) the antinociceptive effects in the hot-plate test. Finally, BAC administration did not modify the aversive motivational state associated to naloxone precipitated NIC withdrawal evaluated by the place aversion conditioning paradigm. These results demonstrated that some acute effects elicited by NIC, but not the aversive motivational consequences of NIC withdrawal can be modulated by the endogenous GABAergic system. Supported  by UBACYT B021 and Ministerio de Ciencia y Tecnología de España                   Presentación en Póster