TY - JOUR
T1 - Companions reverse stressor-induced decreases in neurogenesis and cocaine conditioning possibly by restoring BDNF and NGF levels in dentate gyrus
AU - Tzeng, Wen Yu
AU - Chuang, Jia Ying
AU - Lin, Li Ching
AU - Cherng, Chianfang G.
AU - Lin, Kuei Ying
AU - Chen, Li Hsien
AU - Su, Chien Chou
AU - Yu, Lung
N1 - Funding Information:
This research was supported by ROC NSC grants 97-2321-B-006-010 , 97-2410-H-006-074-MY3 and 98-2410-H-006-019 to L.Y.
Funding Information:
Funding for this study was provided by three grants from ROC National Science Council (NSC) . These ROC NSC grants had no further role in study design, data collection, data analysis, data interpretation, manuscript writing, or decision to submit this manuscript for publication.
PY - 2013/3
Y1 - 2013/3
N2 - The presence of companions can reverse the stressor-induced decrease in neurogenesis in mouse dentate gyrus (DG). In this study, we decided to study the underlying mechanisms of the companions' protective effect and to assess whether two DG neurogenesis-related memories, cocaine-induced conditioned place preference (CPP) and spatial memory, can be affected by our stressor and companions. Neurotrophin levels in DG were measured, in this regard, to reveal their roles in mediating the stressors' and companions' effect. We found that the stressor did not affect NT-3 but acutely decreased NGF and BDNF levels in DG. The presence of companions abolished these stressor-decreased NGF and BDNF levels. Neither the stressor nor the presence of companions affected TrkA, TrkB or TrkC expression in DG. Pre-exposure to the stressor rendered deficits in cocaine-induced CPP and spatial memory, while companions reversed the stressor-decreased cocaine-induced CPP. Intra-ventricular infusion with K252a, a mixed TrkA and TrkB antagonist, did not affect the protective effects of companions on local NGF, BDNF levels in DG, but abolished the companions' protective effects against the stressor-decreased DG neurogenesis and cocaine-induced CPP. Systemic pretreatment with 7,8-dihydroxyflavone (DHF), a selective TrkB agonist, did not affect baseline, the stressor-stimulated corticosterone (CORT) secretion or local NGF, BDNF levels in DG, but in part mimicked companions' protective effects. These results, taken together, indicate that stressor-decreased NGF and BDNF levels in DG could be involved in the stressor-decreased DG neurogenesis and cocaine conditioning. The presence of companions reverses the stressor-decreased DG neurogenesis and cocaine conditioning possibly by restoring BDNF and NGF levels in DG.
AB - The presence of companions can reverse the stressor-induced decrease in neurogenesis in mouse dentate gyrus (DG). In this study, we decided to study the underlying mechanisms of the companions' protective effect and to assess whether two DG neurogenesis-related memories, cocaine-induced conditioned place preference (CPP) and spatial memory, can be affected by our stressor and companions. Neurotrophin levels in DG were measured, in this regard, to reveal their roles in mediating the stressors' and companions' effect. We found that the stressor did not affect NT-3 but acutely decreased NGF and BDNF levels in DG. The presence of companions abolished these stressor-decreased NGF and BDNF levels. Neither the stressor nor the presence of companions affected TrkA, TrkB or TrkC expression in DG. Pre-exposure to the stressor rendered deficits in cocaine-induced CPP and spatial memory, while companions reversed the stressor-decreased cocaine-induced CPP. Intra-ventricular infusion with K252a, a mixed TrkA and TrkB antagonist, did not affect the protective effects of companions on local NGF, BDNF levels in DG, but abolished the companions' protective effects against the stressor-decreased DG neurogenesis and cocaine-induced CPP. Systemic pretreatment with 7,8-dihydroxyflavone (DHF), a selective TrkB agonist, did not affect baseline, the stressor-stimulated corticosterone (CORT) secretion or local NGF, BDNF levels in DG, but in part mimicked companions' protective effects. These results, taken together, indicate that stressor-decreased NGF and BDNF levels in DG could be involved in the stressor-decreased DG neurogenesis and cocaine conditioning. The presence of companions reverses the stressor-decreased DG neurogenesis and cocaine conditioning possibly by restoring BDNF and NGF levels in DG.
UR - http://www.scopus.com/inward/record.url?scp=84875274986&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875274986&partnerID=8YFLogxK
U2 - 10.1016/j.psyneuen.2012.07.002
DO - 10.1016/j.psyneuen.2012.07.002
M3 - Article
C2 - 22832183
AN - SCOPUS:84875274986
SN - 0306-4530
VL - 38
SP - 425
EP - 437
JO - Psychoneuroendocrinology
JF - Psychoneuroendocrinology
IS - 3
ER -
