Effects of single and group housing conditions and alterations in social and physical contexts on amphetamine-induced behavioral sensitization in rats.
Repeated administration of amphetamine (AMPH) can produce behavioral sensitization. However, whether contextual elements and housing conditions influence AMPH-induced behavioral sensitization remains uncertain. This study was designed to examine the effects of housing conditions (single- vs. group-housed) and different contextual changes, including social (with two other co-drug partners) and physical (novel box) context changes, on AMPH-induced behavioral sensitization. During the training phase, all rats were exposed for 7 days to AMPH (1mg/kg, intraperitoneally) in a Locometer chamber, with the exception of animals tested for the effects of physical context changes trained in a novel box. Following a 7-day withdrawal phase, all rats received an AMPH (0.5mg/kg) challenge, and locomotor activity in a Locometer box was recorded before and after AMPH injection during the testing phase. Under group housing conditions, animals exposed to a different physical environment between the training and testing phases or accompanying co-drug partners during the training phase exhibited decreased AMPH-induced locomotor sensitization. In contrast, single housing conditions did not have an inhibitory effect on AMPH-induced behavioral sensitization after manipulations of the physical and social contexts. These results suggest that under group housing conditions, both physical and social context changes can attenuate AMPH-induced behavioral sensitization. The possible neural mechanisms underlying the involvement of different housing conditions in AMPH-induced behavioral sensitization are discussed.
Wang
Ying-Chou
YC
Department of Clinical Psychology, Fu Jen Catholic University, Taipei County 24205, Taiwan.
Wang
Chia-Chuan
CC
Lee
Chin-Cheng
CC
Huang
Andrew Chih Wei
AC
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D004777:Environment; D006799:Housing, Animal; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012931:Social Environment
D000661:Amphetamine