A single episode of maternal deprivation impairs the motivation for cocaine in adolescent mice

Abstract

Our findings demonstrated for the first time that a single episode of early MD can impair the motivation for cocaine consumption in adolescent mice and can be associated with anxiety- and depressive-like behaviour.

Enhancing glutamatergic transmission during adolescence reverses early-life stress-induced deficits in the rewarding effects of cocaine in rats

“…The maternalseparation model is a well-validated early-life stress model which produces distinct phenotypes which are hallmarks of many stressrelated disorders (Ladd et al, 2000;Meaney, 2001;Sanchez et al, 2001). However, the effects of maternal separation on reward function is somewhat controversial with several reports detailing either increased (Flagel et al, 2003;Kosten et al, 2000;Matthews et al, 1999) or decreased reward seeking (Martini and Valverde, 2012;Matthews et al, 1999;Silveira et al, 2010). Here we show that our MS protocol produces a robust deficit in reward processes as indicated by a decrease in cocaine intake.…”

“…It should be noted that this involved extensive handling and repeated IP injections over a three week period during adolescence. It has been well documented that various manipulations to rodents during the early-life period can have profound effects on hedonic behaviour in adulthood (Flagel et al, 2003;Kosten et al, 2000Kosten et al, , 2005Kosten et al, , 2006Lynch et al, 2005;Martini and Valverde, 2012;Matthews et al, 1999;Moffett et al, 2006Moffett et al, , 2007Nylander and Roman, 2013;Silveira et al, 2010;Yajie et al, 2005), as such, we conducted a separate experiment where maternally-separated animals were injected with vehicle alone, while another group of maternallyseparated animals received no injections during the adolescent period. We found the maternal-separation induced reduction in cocaine-taking remained intact independent of whether the animals had received adolescent handling and injections or had not (presented as area under the curve for reasons of succinctness).…”

“…However, this highly-plastic neuronal environment makes the brain highly susceptible to pathological insult (Bondi et al, 2014;Enoch, 2011;Meyer-Lindenberg and Tost, 2012;O'Connor and Cryan, 2014) including psychological stress which has been well established as predisposing individuals to addictive disorders later in life (De Bellis, 2002;Enoch, 2011;Koob, 2008). Indeed, preclinical studies have demonstrated psychological stress induced early in life can affect reward-function in adulthood; both increasing rewardinduced behavioural-reinforcement (Flagel et al, 2003;Kosten et al, 2000;Matthews et al, 1999) and decreasing reward intake, possibly through anhedonia (Martini and Valverde, 2012;Matthews et al, 1999;Silveira et al, 2010). Thus, a need to clarify the mechanisms by which exposure to a psychological stress can alter drug-intake in adulthood remains.…”

Stress, Substance Abuse, and Addiction

“…Prenatal stress is believed to decrease sensitivity to alcohol, which is correlated with alcoholism vulnerability (Campbell et al 2009). Maternal deprivation (MD) in early childhood is believed to alter the reward system significantly enough that one 24-h episode of MD is shown to produce physiological changes similar to depression and anxiety, increasing the time it takes for adolescent mice to meet acquisition criteria for cocaine self-administration (Martini and Valverde 2012).…”

Deneysel Modellerde Anne Yoksunluğunun Beyin ve Davranışlar Üzerine Etkisi

“…Bu testte deneklerin hareketsiz kalma süreleri depresyon benzeri davranış ölçütü olarak kullanılmaktadır. Anne yoksunluğuna maruz kalan yavrularda yetişkin dönemde kuyruk asma testinde hareketsiz kalma süresinin arttığı gösterilmiştir 60 .…”