The Roman High- and Low-Avoidance rat strains differ in fear-potentiated startle and classical aversive conditioning

Psicothema, ISSN 0214-9915, Vol. 21, Nº. 1, 2009, pags. 27-32
Source: OAI

ABSTRACT Las cepas de ratas Roman de alta y baja evitación difieren en respuesta de sobresalto potenciada por miedo y en condicionamiento clásico aversivo. Las sublíneas suizas de ratas Romanas «High»- (RHA/Verh) y «Low»-(RLA/Verh) «Avoidance» han sido seleccionadas genéticamente, desde 1972, en función de su excelente (RHA) o extremadamente pobre adquisición de la tarea de evitación activa en dos sentidos. Cepas consanguíneas (RHA-I y RLA-I), derivadas de las dos líneas anteriores, se mantienen en nuestro laboratorio desde 1997. En comparación con la cepa RHA-I, la cepa RLA-I muestra incrementos en las respuestas hormonales al estrés, así como en conductas de ansiedad/miedo en una variedad de pruebas y variables conductuales incondicionadas. Hasta la fecha, las cepas de ratas Romanas no han sido comparadas en procedimientos de condicionamiento clásico de miedo a contextos o estímulos discretos. El presente trabajo tuvo como objetivo comparar ambas en 1) dos procedimientos de medida de la respuesta de sobresalto potenciada por miedo; y, 2) en un procedimiento de condicionamiento clásico de miedo (petrificación condicionada). Los resultados indican que las ratas RLA-I muestran niveles mayores de condicionamiento de miedo (respuesta de sobresalto y respuesta de petrificación) que las RHA-I, reforzando así los perfiles diferenciales de ansiedad/miedo de las dos cepas.

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