Faculty Collaboration Database

Chronic psychosocial stress decreases calcineurin in the dentate gyrus: a possible mechanism for preservation of early ltp. Neuroscience 2003;117(4):869-74

Date

03/26/2003

Pubmed ID

12654339

DOI

10.1016/s0306-4522(02)00766-2

Scopus ID

2-s2.0-0037430759 (requires institutional sign-in at Scopus site)   36 Citations

Abstract

Chronic psychosocial stress impairs early long-term potentiation (LTP) in the hippocampal CA1 region but not in the dentate gyrus of anesthetized rats. Analysis of putative signaling molecules involved in the expression of LTP was performed to determine the possible reason(s) for the apparent resistance of the LTP of the dentate gyrus to chronic psychosocial stress. Immunoblotting was used to determine possible changes in the basal levels of various fractions of calcium-dependent calmodulin kinase II (CaMKII), phosphorylated CaMKII (P-CaMKII), calmodulin, protein kinase C gamma (PKCgamma) and calcineurin in the dentate gyrus of chronically stressed rats. Western blot analysis revealed that chronic stress significantly decreased the levels of the total CaMKII without affecting P-CaMKII levels. No significant change was detected in the levels of the upstream effectors, calmodulin and PKCgamma. However, chronic stress produced a significant decrease in calcineurin levels. The data suggest that the dentate gyrus of chronically stressed rats may have developed a compensatory mechanism whereby calcineurin levels are reduced to maintain normal P-CaMKII levels, which may be responsible for the normal early LTP of the dentate gyrus of chronically stressed rats. The results of this work will increase understanding of why certain brain regions are more resistant to deleterious effects of conditions that deteriorate learning and memory.

Author List

Gerges NZ, Aleisa AM, Schwarz LA, Alkadhi KA

Author

Nashaat Gerges PhD Chair, Professor in the School of Pharmacy Administration department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Calcineurin
Calcium Signaling
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Calcium-Calmodulin-Dependent Protein Kinases
Calmodulin
Cell Membrane
Chronic Disease
Cytosol
Dentate Gyrus
Down-Regulation
Immunoblotting
Long-Term Potentiation
Male
Memory Disorders
Neurons
Phosphorylation
Protein Kinase C
Rats
Rats, Wistar
Social Behavior
Stress, Psychological
Subcellular Fractions