Compound that may treat chronic itch identified

Scientists have identified a class of compounds that can stop chronic itch without the adverse side effects normally associated with medicating the condition.
"Chronic intractable itch" in which the itchy sensation never goes away is a difficult-to-treat condition closely associated with dialysis and renal failure.
"Our lab has been working on compounds that preserve the good properties of opioids and eliminate many of the side effects," said Professor Laura Bohn from the Florida campus of The Scripps Research Institute (TSRI).
"The new paper describes how we have refined an aspect of signalling underlying how the drugs work at the receptor so they still suppress itch and do not induce sedation.

"Developing compounds that activate the receptors in this way may serve as a means to improve their therapeutic potential," she said.
The study, which was published in the journal Neuropharmacology, used a compound called isoquinolinone 2.1 to target the kappa opioid receptor, which is widely expressed in the central nervous system and serves to moderate pain perception and stress responses.
The compound was effective in stopping irritant-induced itch, without causing sedation, in mouse models of the condition.
Bohn noted isoquinolinone 2.1 is one example of a new class of "biased" kappa agonists that avoid many central nervous system side effects by preferentially activating a G protein-mediated signalling cascade without involving another system based on beta-arrestin protein interactions.