Aller au contenuAller au menuAller à la recherche

Marian Joels"Stress and limbic cell function: importance of time, region and life history"

Abstract :

Stress exposure leads to increased levels of circulating adrenaline and corticosteroid hormones. The steroids easily enter the brain and target neurons enriched with receptors. Part of these receptors seems to be located in the plasma membrane, mediating rapid non-genomic actions. It is thought that these rapid-onset actions, in close interaction with noradrenaline, contribute to encoding of stress-related emotional and neutral information. In agreement, elevated levels of corticosteroid hormones in humans, linked in time to encoding, promote memory formation particularly of emotional and context-related information. Shortly after stress, corticosteroids also start a gene-mediated cascade through their nuclear receptors which several hours later changes the function of limbic neurons, in a region-specific manner. The delayed effects are hypothesized to primarily serve as a means to normalize neuronal activity after stress and to preserve earlier encoded information.
Both rapid and delayed corticosteroid actions can be modulated by life events (such as repetitive, uncontrollable stress). The impact of corticosteroid exposure on limbic cell function is particularly sensitive to stressful circumstances experienced early in life and/or maternal care.

Selected publications

Pu Z, Krugers HJ, Joëls M. beta-adrenergic facilitation of synaptic plasticity in the rat basolateral amygdala in vitro is gradually reversed by corticosterone. Learn Mem. 2009 16(2):155-60.
Joëls M, Karst H, DeRijk R, de Kloet ER. The coming out of the brain mineralocorticoid receptor. Trends Neurosci. 2008 31(1):1-7.
Champagne DL, Bagot RC, van Hasselt F, Ramakers G, Meaney MJ, de Kloet ER, Joëls M, Krugers H. Maternal care and hippocampal plasticity: evidence for experience-dependent structural plasticity, altered synaptic functioning, and differential responsiveness to glucocorticoids and stress. J Neurosci. 2008 28(23):6037-45.
Joëls M, Pu Z, Wiegert O, Oitzl MS, Krugers HJ. Learning under stress: how does it work? Trends Cogn Sci. 2006 10(4):152-8.
Karst H, Berger S, Turiault M, Tronche F, Schütz G, Joëls M. Mineralocorticoid receptors are indispensable for nongenomic modulation of hippocampal glutamate transmission by corticosterone. Proc Natl Acad Sci U S A. 2005 102(52):19204-7.