Mechanisms of Itch Evoked by β-Alanine

作者：Qin Liu, Parul Sikand, Chao Ma, Zongxiang Tang, Liang Han, Zhe Li, Shuohao Sun, Robert H. LaMotte, Xinzhong Dong · 发表于：Journal of Neuroscience · 年份：2012 · DOI：10.1523/jneurosci.3509-12.2012 · 被引用次数：333 · 研究领域：Biochemical effects in animals、Neuroendocrine regulation and behavior、Olfactory and Sensory Function Studies

β-Alanine, a popular supplement for muscle building, induces itch and tingling after consumption, but the underlying molecular and neural mechanisms are obscure. Here we show that, in mice, β-alanine elicited itch-associated behavior that requires MrgprD, a G-protein-coupled receptor expressed by a subpopulation of primary sensory neurons. These neurons exclusively innervate the skin, respond to β-alanine, heat, and mechanical noxious stimuli but do not respond to histamine. In humans, intradermally injected β-alanine induced itch but neither wheal nor flare, suggesting that the itch was not mediated by histamine. Thus, the primary sensory neurons responsive to β-alanine are likely part of a histamine-independent itch neural circuit and a target for treating clinical itch that is unrelieved by anti-histamines.