Source: Karolinska Institutet
Summary: Researchers have discovered a new
sensory organ that is able to detect painful mechanical damage, such as pricks
and impacts.
Researchers at Karolinska Institutet in
Sweden have discovered a new sensory organ that is able to detect painful
mechanical damage, such as pricks and impacts. The discovery is being published
in the journal 'Science'.
Pain causes suffering and results in
substantial costs for society. Almost one person in every five experiences
constant pain and there is a considerable need to find new painkilling drugs.
However, sensitivity to pain is also required for survival and it has a
protective function. It prompts reflex reactions that prevent damage to tissue,
such as pulling your hand away when you feel a jab from a sharp object or when
you burn yourself.
Researchers at Karolinska Institutet have now
discovered a new sensory organ in the skin that is sensitive to hazardous
environmental irritation. It is comprised of glia cells with multiple long
protrusions and which collectively go to make up a mesh-like organ within the
skin. This organ is sensitive to painful mechanical damage such as pricks and
pressure.
The study describes what the new pain-sensitive organ looks like, how it is organised together with pain-sensitive nerves in the skin and how activation of the organ results in electrical impulses in the nervous system that result in reflex reactions and an experience of pain. The cells that make up the organ are highly sensitive to mechanical stimuli, which explain how they can participate in the detection of painful pinpricks and pressure. In experiments, the researchers also blocked the organ and saw a resultant decreased ability to feel mechanical pain.
"Our study shows that sensitivity to
pain does not occur only in the skin's nerve fibres, but also in this
recently-discovered pain-sensitive organ. The discovery changes our
understanding of the cellular mechanisms of physical sensation and it may be of
significance in the understanding of chronic pain," says Patrik Ernfors,
professor at Karolinska Institutet's Department of Medical Biochemistry and
Biophysics and chief investigator for the study.