Involvement of the Sigma1 Receptor in the Appetitive Effects of Cocaine (original) (raw)

Cocaine induces in the brain a drastic plasticity affecting numerous neurotransmission systems. In turn, the drug provokes a complex pattern of behavioral responses, including locomotor hyperactivity, stereotyped behaviors, sensitization, and appetitive and reinforcing properties that rapidly generate the addictive process. The involvement of σ1 receptors in cocaine effects has been suggested initially through the observation that σ1 antagonists could attenuate several acute effects induced by the drug, such as hyperlocomotion, stereotypies, convulsions and lethality. We will describe thereafter the recent results showing that activation of the σ1 receptor is also involved in the appetitive properties of cocaine, as measured using place preference conditioning in mice. Using selective σ1 antagonists or an in vivo antisense strategy, the role of the σ1 receptor in acquisition, expression and reactivation of conditioned place preference was demonstrated. The observation that repeated administration of cocaine rapidly provokes overexpression of the σ1 receptor outlines its major role in these first psychological steps of addictive processes. The physiological interaction between cocaine and σ1 receptors is detailed and the possibility that effective therapeutical strategies could target the σ1 receptor is considered.

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Dr. T. Maurice

CNRS FRE 2693

University of Montpellier II

cc 090

place Eugène Bataillon

34095 Montpellier cedex 5

France

Phone: +33/0 4 67 14 36 23

Fax: +33/0 4 67 14 42 51

Email: maurice@univ-montp2.fr