Withdrawal and avoidance behavior are common symptoms of depression and can appear as a consequence of absence of reward, i.e. extinction-induced depression (EID). This is particularly relevant for the aged organism subjected to pronounced loss of former rewards. Avoidance of the former site of reward and increased withdrawal into a distant compartment accompany extinction of food-rewarded behavior in rodent models. During extinction, behavioral markers for re-learning dissociate from indicators of extinction-induced depression. Here we examined the effect of a chronic treatment with corticosterone (CORT), a well-known inducer of depression-related behavior, on EID in adult and aged rats. Adult (3-4months) and aged (18months) male rats were treated with CORT via drinking water for 3weeks prior to extinction of a cued food-reward task. CORT treatment increased the distance from the site of reward and decreased goal tracking behavior during extinction, especially in the aged rats. Plasma hormone levels measured before and after restraint stress showed a decline in basal ACTH- and CORT-levels after chronic CORT treatment in aged animals. The treatment significantly impaired the HPA-axis activation after acute stress in both, adult and aged animals, alike. Altogether, these findings show an enhancement of EID after chronic CORT treatment in the aged organism, which may be mediated by an impaired HPA-axis sensitivity. These findings may have special relevance for the investigation of human geriatric depression.
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http://dx.doi.org/10.1016/j.yhbeh.2016.09.003 | DOI Listing |
Neuropsychopharmacology
January 2022
Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
Current pharmacotherapies for posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) are ineffective for many patients, and often do not restore cognitive dysfunction associated with these disorders. Behavioral therapies, such as exposure therapy, can be effective for treatment-resistant patients. The mechanisms underlying exposure therapy are not well-understood.
View Article and Find Full Text PDFMol Ther Nucleic Acids
March 2020
Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, China; Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China. Electronic address:
We previously found that cocaine abuse could increase microRNA134 (miR134) levels in the hippocampus; yet the roles of miR134 in cocaine-related abnormal psychiatric outcomes remain unknown. In this study, using the cocaine-induced conditioned place preference (CPP) mice model, we found that mice exhibit enhanced anxiety-like and depression-like behaviors during the cocaine extinction (CE) period of CPP, accompanied by obviously increased miR134 levels and decreased levels of 19 genes that are associated with synaptic plasticity, glia activity, and neurochemical microenvironments, in the ventral hippocampus (vHP). Knockdown of miR134 in vHP in vivo reversed the changes in 15 of 19 potential gene targets of miR134 and rescued the abnormal anxiety-like and depression-like behavioral outcomes in CE mice.
View Article and Find Full Text PDFHorm Behav
November 2016
Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
Withdrawal and avoidance behavior are common symptoms of depression and can appear as a consequence of absence of reward, i.e. extinction-induced depression (EID).
View Article and Find Full Text PDFJ Neurochem
May 2016
Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
Reward-dependent instrumental behavior must continuously be re-adjusted according to environmental conditions. Failure to adapt to changes in reward contingencies may incur psychiatric disorders like anxiety and depression. When an expected reward is omitted, behavior undergoes extinction.
View Article and Find Full Text PDFNeuropsychopharmacology
December 2015
School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea.
Various subtypes of metabotropic glutamate receptors (mGluRs) have been implicated in fear extinction, but mGluR2/3 subtype has not been tested. Here, we found that microinjection of an mGluR2/3 antagonist, LY341495, into the lateral amygdala (LA), but not into the adjacent central amygdala (CeA), impaired extinction retention without affecting within-session extinction. In contrast, we failed to detect any significant changes in motility and anxiety during a period when extinction training or retention was performed after LY341495 injection, suggesting that the effect of LY341495 is specific to conditioned responses.
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