An Indian scientist at the Queensland Brain Institute has revealed that stress is the key to alleviating pain.
The research led by Pankaj Sah explained a key mechanism by which the stress hormone called noradrenalin, in stressful events affects the brain's pain-processing pathway to produce analgesia.
The researchers studied a region of the amygdala, the brain's emotion-processing region that mediates the emotional and stress-related aspects of pain. Sah and colleagues sought in their studies to understand the mechanism by which noradrenaline influences neuronal transmission of pain inputs from the brainstem region known as the pontine parabrachial (PB).
In their experiments with rats, the researchers analyzed the effects of the stress hormone on electrical stimulation of the pathway between the brainstem region and amygdala. They found that that the hormone acted as a powerful suppressor of that stimulation.
"Our results show that an important mediator of stress-induced analgesia could be the potent modulation by noradrenaline of [pain] PB inputs in the central amygdala," the researchers concluded.
The findings have been published in the December 6, 2007, issue of the journal Neur, published by Cell Press.