Stress Triggered Changes in Expression of Genes for Neurosecretory Granules in Adrenal Medulla
With acute stress, the release of adrenomedullary catecholamines is important for handling the emergency situation. However, when chronic or repeated, stress alters the allostatic load and leads to a hyperadrenergic state, resulting in the development or worsening of a wide range of diseases. To hel...
Gespeichert in:
Veröffentlicht in: | Cellular and molecular neurobiology 2012-07, Vol.32 (5), p.795-800 |
---|---|
Hauptverfasser: | , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | With acute stress, the release of adrenomedullary catecholamines is important for handling the emergency situation. However, when chronic or repeated, stress alters the allostatic load and leads to a hyperadrenergic state, resulting in the development or worsening of a wide range of diseases. To help elucidate the mechanism, we examined the effects of single and repeated immobilization stress on gene expression of components of neurosecretory vesicles in the adrenal medulla. Male Sprague–Dawley rats were exposed to immobilization stress once for 2 h (1× IMO) or daily for six consecutive days (6× IMO). Compared to unstressed controls, 1× IMO elevated gene expression of vesicular monoamine transporter 2 (VMAT2). In response to 6× IMO, not only was VMAT2 mRNA still elevated, but chromogranin A (CgA) and chromogranin B (CgB) mRNAs were also increased two to three-fold above basal levels. To investigate the possible role of the hypothalamic–pituitary–adrenal axis in the induction of VMAT2, PC12 cells were treated with the synthetic glucocorticoid dexamethasone, which was found to elevate VMAT2 mRNA expression. The findings suggest that following repeated stress, elevations of various components of neurosecretory vesicles in the adrenal can facilitate more efficient utilization of the well-characterized heightened catecholamine levels. |
---|---|
ISSN: | 0272-4340 1573-6830 1573-6830 |
DOI: | 10.1007/s10571-011-9785-z |