痒觉神经机制的研究近年取得突破性进展，但对初级感觉神经元水平调控机制的认识仍然处于起步阶段。研究表明，肿瘤抑制基因PTEN特异地表达在脊髓背根神经节（DRG）的IB4阳性细胞内，提示PTEN可能参与躯体感觉的调控。为了避开胚胎阶段基因敲除对神经元发育的影响，从而清晰地研究成年时期DRG细胞内PTEN的作用，我们采用可诱导的条件性基因敲除策略，制备了Drg11-CreER;PTENflox/flox小鼠，在小鼠成年时期给予他莫昔芬处理，可敲除DRG的IB4阳性细胞内的PTEN。初步的结果显示：PTEN条件性敲除小鼠出现皮损和自发痒行为以及显著增强的诱发痒行为，但痛行为并不受影响。我们将在此基础上进一步以行为学、形态学和电生理学、钙成像等手段研究PTEN在初级感觉神经元水平特异性调控痒觉传递的细胞和分子机制。本研究将深入揭示痒觉产生的神经学机理，并为临床开发抑制瘙痒的药物提供理论依据。

Recently, a huge progress has been made towards elucidating the mechanisms underlying itch transmission. However, the study for the fully understanding of the mechanism at primary sensory neurons is still needed. It has been reported that PTEN, a tumor suppressor gene, are specifically expressed in IB4-positive neuron of DRG (dorsal root ganglia) in mice suggesting a potential role of PTEN in mediating and modulating of somatosensation. In order to avoid any interference of embryonic development and investigate the role of PTEN in modulation of itch and pain, we generated Drg11-CreER;PTENflox/flox mice. In this mice, PTEN can be inducibly knocked out in DRG IB4-expressing neurons after the mice being treated with Tamoxifen in adulthood. According to the preliminary data, the CKO mouse showed skin lesion and spontaneous itch behavior and an increase of pruritogen-induced itch behavior, but normal pain sensation. Next, we plan to investigate the specific neuronal and molecular mechanisms of PTEN on the itch transmission at DRG neurons. Our study will contribute to the understanding of itch transmission mechanism and be helpful for the development of new anti-itch drug.