Impulsivity characterization in the Roman high- and low-avoidance rat strains: behavioral and neurochemical differences.
The selective breeding of Roman high- (RHA) and low-avoidance (RLA) rats for rapid vs extremely poor acquisition of active avoidance behavior in a shuttle-box has generated two phenotypes with different emotional and motivational profiles. The phenotypic traits of the Roman rat lines/strains (outbred or inbred, respectively) include differences in sensation/novelty seeking, anxiety/fearfulness, stress responsivity, and susceptibility to addictive substances. We designed this study to characterize differences between the inbred RHA-I and RLA-I strains in the impulsivity trait by evaluating different aspects of the multifaceted nature of impulsive behaviors using two different models of impulsivity, the delay-discounting task and five-choice serial reaction time (5-CSRT) task. Previously, rats were evaluated on a schedule-induced polydipsia (SIP) task that has been suggested as a model of obsessive-compulsive disorder. RHA-I rats showed an increased acquisition of the SIP task, higher choice impulsivity in the delay-discounting task, and poor inhibitory control as shown by increased premature responses in the 5-CSRT task. Therefore, RHA-I rats manifested an increased impulsivity phenotype compared with RLA-I rats. Moreover, these differences in impulsivity were associated with basal neurochemical differences in striatum and nucleus accumbens monoamines found between the two strains. These findings characterize the Roman rat strains as a valid model for studying the different aspects of impulsive behavior and for analyzing the mechanisms involved in individual predisposition to impulsivity and its related psychopathologies.
Moreno
Margarita
M
Departamento de Neurociencia y Ciencias de la Salud, Universidad de Almería, Almería, Spain.
Cardona
Diana
D
Gómez
Maria José
MJ
Sánchez-Santed
Fernando
F
Tobeña
Adolf
A
Fernández-Teruel
Alberto
A
Campa
Leticia
L
Suñol
Cristina
C
Escarabajal
Maria Dolores
MD
Torres
Carmen
C
Flores
Pilar
P
D000818:Animals; D001362:Avoidance Learning; D015306:Biogenic Monoamines / Q000378:metabolism; D003216:Conditioning, Operant; D003342:Corpus Striatum / Q000378:metabolism*; D004327:Drinking Behavior; D005260:Female; D007175:Impulsive Behavior / Q000378:metabolism*; D023421:Models, Animal; D009483:Neuropsychological Tests; D009714:Nucleus Accumbens / Q000378:metabolism*; D010641:Phenotype; D051381:Rats; D011930:Reaction Time; D012201:Reward; D013045:Species Specificity; D013997:Time Factors
D015306:Biogenic Monoamines