Role of Wnt/b-catenin signaling pathway in the expression of cocaine induced sensitization

BATUECAS, JORGELINA A.; CUESTA, SANTIAGO; SEVERIN, MA. JULIA; ROSSO, SILVANA B; PACCHIONI, ALEJANDRA M

Congreso; XXVII Congreso Anual de la Sociedad Argentina de Investigaciones en Neurociencias; 2012

Wnt factors are cistein rich secreted proteins that interact with their receptors: Frizzled, Ryk, and Ror. As a result of the interaction, Dishevelled (DVL) is activated, and consequently, one of three pathways: Wnt/b-catenin, Planar Cell Polarity, or Wnt/calcium pathways. Wnt signaling pathways are essential for development of the mammalian brain. However little is known regarding its role in adulthood. Our main goal is to elucidate if the Wnt/b-catenin signaling pathway participates in cocaine sensitization. Therefore, adult male Wistar rats received cocaine injections daily for a week and then a challenge three weeks later. Locomotor activity was recorded on Day 1, 7 and 28. Our rats chronically treated with cocaine showed a significant increase in locomotor activity when comparing Day 28 to Day 1, as it was previously demonstrated. Twenty four hours after cocaine challenge on Day 28 rats were sacrificed, and brains areas were dissected to study b-catenin expression levels. Our data showed changes in b-catenin expression only in the Nucleus Accumbens (NAcc) of animals that showed cocaine sensitization on Day 28, while no changes were found in Prefrontal Cortex. So far our data suggests that b-catenin in NAcc is involved in the expression of cocaine induced sensitization. Research supported by: PICT 2008-227(National Agency of Scientific Promotion; Argentina)