New research reveals on stress hormones act on the brain read more at here www.spinonews.com/index.php/item/993-new-research-reveals-on-stress-hormones-act-on-the-brain

Stress is a common problem often resulting in poor health and mental disorders. New research has revealed that how to stress hormones act on the brain may need to be reassessed.

Biotechnology and Biological Sciences Research Council (BBSRC)study, has found that the action of mineralocorticoid receptors (MRs) at the neuronal genome cannot be predicted based solely on receptor occupancy by glucocorticoid hormone.

Professor Hans Reul together with Dr. Karen Mifsud, of the University's School of Clinical Sciences, investigated the actual binding of MRs and glucocorticoid receptors (GRs) to genes in the hippocampus after stress.

To their surprise they found the binding of MRs to genes was not constantly high, but actually low under non-stress conditions and increased substantially after stress.

However, GRs followed the expectation that binding to target genes would be minimal under baseline conditions and increase dramatically after stress following the GR binding profile to glucocorticoids.

Hans Reul, Professor of Neuroscience, said, the findings are a significant step forward in our understanding of how glucocorticoid hormones act on the brain after stressful events. 

Their work provides the first strong evidence in vivo that MR and GR are heterodimerising and that MRs may require the presence of GRs in order to bind to specific target genes.

Thirty years ago, Professor Reul, who was working at Utrecht University in The Netherlands, observed that glucocorticoids exert their effects on the brain via two different types of receptors, the MRs and the GRs.

Reul discovered that due to their extraordinarily high affinity for glucocorticoids, MRs are always fully occupied by these hormones, whereas GRs, as a result of their lower binding affinity, only became occupied after a stressful event.

Based on these results, the concept was launched that MRs have a constant action on brain function, whereas GRs mediated negative feedback and enhance learning and memory after stress.