Hunger cures chronic pain
Pain is very important for the body. It signals problems that require immediate correction or treatment. For example, due to pain, a person abruptly pulls his hand away from a hot stove and protects it from a deep burn.
But there is another type of pain that exhausts the body and requires long-term use of drugs that stop it. Chronic pain does not have a signaling and protective function.
A group of neuroscientists from the University of Pennsylvania has proved that the central nervous system is able to suppress chronic pain if an animal is hungry.
They identified a group of 300 neurons that switch priority to hunger, weakening the perception of pain. This tiny part of the brain can be used as a target for the treatment of chronic pain from old injuries or chronic inflammatory processes.
The researchers compared the reactions of laboratory mice that were not fed for 24 hours to acute and chronic pain. The goal was to evaluate the perception of pain in a state of hunger.
It is noteworthy that hungry mice reacted to acute pain in the same way as their well-fed counterparts.
As for chronic pain, it was dulled in hungry mice. They behaved like well-fed mice who received an analgesic drug, and boldly ran to the place where they were exposed to pain. Well-fed mice avoided him.
Next, the researchers determined which part of the brain is responsible for the perception of pain in a hungry state. It is known that agouti-related protein (agouti-related protein, AgRP), is involved in the formation of hunger. Stimulation of the neurons in which it is produced led to a decrease in sensitivity to chronic pain, the reaction to acute pain did not change.
To obtain more specific information about the mechanisms of hunger and pain perception, the researchers stimulated groups of neurons synthesizing individual subpopulations of AgRP in turn. Thus, it was possible to identify a group of 300 neurons located in the parabrachial nucleus of the brain stem. These neurons significantly suppressed the perception of chronic pain.
Scientists went further and identified a neurotransmitter (neuropeptide Y, NPY) that selectively inhibited the transmission of impulses from pain receptors. Blocking of Y1 receptors interacting with NPY led to the opposite effect and restoration of full perception of chronic pain.
The potential of the discovery is impressive: now a target has been identified, the impact of which can selectively treat chronic (inflammatory or post-traumatic) pain, without changing the perception of acute pain, which is necessary for the survival of the body.
Article by A. L. Alhadeff et al. A Neural Circuit for the Suppression of Pain by a Competing Need State is published in the journal Cell.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the University of Pennsylvania: Being hungry shuts off perception of chronic pain.