Reduced Avoidance Coping In Male, But Not In Female Rats, After Mild Traumatic Brain Injury: Implications For Depression.

Reduced Avoidance Coping In Male, But Not In Female Rats, After Mild Traumatic Brain Injury: Implications For Depression. Behav Brain Res. 2019 Jul 03;:112064 Authors: Avcu P, Sinha S, Pang KCH, Servatius RJ Abstract Although there is evidence that traumatic brain injury (mTBI) induces emotional sequelae in rats, it is unclear whether the phenotype is reminiscent of major depressive disorder (MDD) or posttraumatic stress disorder (PTSD). Three behavioral protocols with oppositional indicators for MDD or PTSD were assessed: acoustic startle responses (ASRs), eyeblink conditioning, and instrumental escape/avoidance (E/A) learning. Female and male rats were exposed to lateral fluid percussion injury (LFPi) consistent with mild TBI (mTBI) or sham (SHAM) surgery. Experiment 1 suggested that the acquisition of the classically conditioned eyeblink responses were unaffected by mTBI in neither female nor male rats. In Experiment 2, both male and female mTBI rats acquired instrumental escape responses similar to their SHAM counterparts. Avoidance expression of female mTBI rats did not differ appreciably from female SHAM rats. However, male mTBI rats expressed avoidance at a lower rate than male SHAM rats over training. Poor coping in male rats emerged with repeated exposure to stress, suggesting that depressive behaviors in mTBI develop over time and with continued demand from stress. Severely attenuated ASRs were evident in female and male mT...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research