Kontakt 2010, 12(1):100-104 | DOI: 10.32725/kont.2010.012

Role of glutamate in neurodegenerative changes in the hippocampus caused by stressBiomedicine

Petr Zach^1,3,*, Jana Mrzílková³, Karel Valeš²

¹ Jihočeská univerzita v Českých Budějovicích, Zdravotně sociální fakulta, katedra preklinických oborů

² Fyziologický ústav AV ČR, v. v. i., Praha

³ Anatomický ústav 3. LF UK, Praha

The experimental use of corticoids is focused on simulation of processes commonly occurring in the organism or in the treatment with these substances. High corticoid levels exert negative effects particularly on memory structures of the CNS such as the hippocampus. High glucocorticoid levels reduce CRH levels through the feedback loop mechanism. In contrast, elevated CRH levels negatively affect the amount of glucocorticoids circulating in the blood. In a number of diseases (as for example posttraumatic stress disorder or Alzheimer disease) there are high levels of glucocorticoids. Glucocorticoids are mediators of the stress reaction (flight or fight) in agreement with the activation of sympathetic part of the autonomous nervous system. In the evolution, the system made the organism possible to escape particularly from a physical danger (for example primeval man was pursued by a tiger). This system is currently by far not adapted to the rapidly varying conditions of the life. A number of sedentary occupations do not make it possible to use it in an optimum way. It is perhaps possible that this is a reason for maladaptive patterns of the stress reaction manifested in chronic stress by diabetes, hypertension, dementia and further so called civilization diseases. One of possibilities of investigating these processes is the animal stress model in laboratory rats. Groups of animals are administered for a certain period with CRH and/or glucocorticoids and compared to controls. After completing the experiment, we search for morphological changes in the CNS (volumetric reduction in the hippocampus) or follow behavioural changes over time. The most severe damage occurs in the group administered with glucocorticoids compared with the group receiving CRH only or that administered with CRH + glucocorticoids. This investigation can be used to understand further processes occurring at cellular or subcellular level.

Keywords: hippocampus; stress; glucocorticoids; CRH; behavioural; civilization diseases

Published: March 31, 2010  Show citation