Why the skin itches from light touches

The touch of an insect that has sat on the skin gives a tickling sensation, and sometimes a severe itch. This reaction is known as mechanical itching, it is not induced by chemicals, unlike other types of pruritus caused by contact with animals. While the chemical aspect of the problem has been widely studied by scientists, the cause of mechanical "scabies" is much less clear. But now the researchers were able to trace the pattern of the appearance of both a chemical and a mechanical stimulus.

Susceptibility to chemical irritants

If one person just scratches the problem area a little, then another person can scrabble this place in fury, but never relieve the symptom. Why is this happening? In humans, there is a different susceptibility to allergens and chemicals. Therefore, antihistamines are intended to alleviate uncontrolled pruritus. Physicians say that it is the histamine compounds that are responsible for the occurrence of severe itching. However, not always medicines can help in solving the problem. This observation prompted scientists to think about another source of uncontrolled pruritus. Probably, there is an alternative way of transferring information to the brain.

A special group of neuropeptides

A new study opened the eyes of scientists. In neurons of the spinal cord there is a special way for the occurrence of mechanical itching. So, interneurons are responsible for transmitting sensory information, which gives the skin to the brain. Neurotransmitter, or neuropeptide Y, and was found by scientists as interneurons of the spinal cord. Previously, scientists knew about his presence in the spinal cord and brain, but were not sure of his functions.

The experience in mice

Now, researchers have suggested that neuropeptide Y has a function similar to "gate control." Scientists have selectively removed this group of neurotransmitters from the spinal cord of mice. Two weeks later the rodents began to scratch their own body uncontrollably, even from a light touch. At the same time, toxic allergens did not cause such a reaction. This experiment allowed scientists to establish separate ways of occurrence for chemical and mechanical stimuli.

Conclusion

The specialists did not stop at the achieved result and went further. The next discovery was the discovery of a difference in light touch to the skin, covered with hairs, and to absolutely smooth skin, for example on the palms or feet. Skin covered with hairs, inhibits signals coming from neurons. Doctors hope that this information will help in creating the drug to alleviate the suffering of sensitive people feeling the lack of neuropeptide Y.