Distinct phenotypes of spontaneous activity and induction of amphetamine sensitization in inbred Roman high- and low-avoidance rats: Vulnerability and protection. (23rd April 2018)

• Record Type: Journal Article
• Authors: Giménez-Llort, Lydia; Guitart-Masip, Marc; Tobeña, Adolf; Fernández-Teruel, Albert; Johansson, Björn
• Is Part Of: Neuroscience letters. Volume 673(2018)
• Page Start: 92
• Page End: 98
• Publication Date: 2018-04-23
• Subjects: Amphetamine sensitization -- Vulnerability -- Induction -- Inbred roman rats -- Locomotor activity -- Habituation -- Spontaneous activity -- Animal model; Neurology -- Periodicals; Neurology -- Periodicals; Research -- Periodicals; Neurologie -- Périodiques; Neuroanatomie -- Périodiques; Neuropharmacologie -- Périodiques; Neurophysiologie -- Périodiques; Neurology; Periodicals; Electronic journals; 617.48
• DOI: 10.1016/j.neulet.2018.03.011
• Languages: English
• ISSNs: 0304-3940

Abstract

Highlights: Inbred Roman rats show distinct phenotypes of amphetamine-induced behavioral sensitization. Inbred RLA rats are insensitive to induction of amphetamine sensitization. Inbred RHA rats are more vulnerable to behavioral sensitization than Sprague-Dawley rats. Inbred Roman rats show higher acute and long-term spontaneous activity than Sprague-Dawley rats. Spontaneous activity as a covariant allows to reveal the distinct induction of sensitization phenotypes. Abstract: The psychogenetically selected Roman high- (RHA) and low-avoidance (RLA) rats are being proposed as a valuable animal model of individual vulnerability to the two distinct neurobiological mechanisms of behavioral sensitization to psychostimulants, namely induction and expression. Most hallmarks of their divergent phenotypes are also found in the inbred RHA (RHA-I) and RLA (RLA-I) strains. For instance, they differ in the expression of sensitization to amphetamine. However, the pattern of spontaneous activity of the inbred rats seems to differ from that of outbred Roman strains. The present work shows the relevance of analyzing spontaneous activity as a covariant in order to determine the significance of day effect in the induction of behavioral sensitization to amphetamine (regime: 11 days, 1 mg/kg, i.p.) in the inbred strains and, for comparison, the standard low activity Sprague-Dawley (SD) strain. Our results also confirm that, in parallel to the outbred strains, only inbred RHA rats showed sensitization during the induction phase, here detectable from day 9 of treatment, while RLA-I and SD strains did not. Inbred RLA rats provide an interesting model to study individual resistance to sensitization, with nuances due to their underlying high spontaneous activity phenotype.