Thaindian News

Washington, May 19 (IANS) Scientists have been able to block the pain and numb feeling that lingers long in the gums after a visit to the dentist - thanks to chilli peppers. Harvard researchers combined an inactive derivative of a local anaesthetic called QX314 with capsaicin - the pain-producing agent in chilli peppers - to produce the blocking effect.

Capsaicin works by opening channels present only in pain fibres to allow QX314 only into these cells where it blocks their function, said Clifford Woolf, who led the study.

“This is the first example of using the body’s own cellular channels as a drug delivery system, targeting treatment only at pain fibres,” he was quoted as saying by ScienceDaily.

“These common analgesics, including QX314, however, affect all neurons in the treated area,” Woolf said.

Consequently, they block both the pain and the touch receptors, producing numbness. Neurons, controlling muscles, are silenced as well, producing a temporary paralysis.

In a bid to block pain receptors and leave touch sensors and motor function unharmed, scientists used a normally inactive QX314.

Since local anaesthetics only operate inside neurons, an injection of QX314 alone is ineffective. As QX314 only enters pain neurons and, thereby, acts exclusively as a painkiller, the researchers combined it with capsaicin.

Capsaicin binds a membrane receptor only present in the membrane of neurons responsible for pain perception.

Thus, the chilli pepper opens channels, enabling QX314 to get into the cell and then block the pain receptors.

Using rats, the scientists could show that when applied to the animals’ hind paws, the combination of QX314 and capsaicin exclusively blocks pain receptors.