美国哈佛医学院David D. Ginty研究小组发现，脑干中的机械感受器突触塑造触觉的中央表征。2021年10月11日，《细胞》杂志在线发表了这项成果。

研究人员发现，在产后发育过程中，外围机械感受器与脑干中枢目标之间的第一个突触出现了无毛皮肤的不成比例表征。机械感受器的突触在发育过程中不断完善，这取决于其终端与无毛皮肤的接近程度，因此，那些支配无毛皮肤的突触连接会扩大其中央表征。在不能感知轻柔触觉的小鼠中，支配无毛皮肤的机械感受器仍然在脑干中产生更强大的突触。研究人员提出，机械感受器支配的皮肤区域控制着其中央突触的发育细化，进而塑造大脑中的触摸表征。

据悉，哺乳动物利用其手和脚的无毛皮肤来导航和操纵它们的环境。不同物种体表的皮层图包含了大量的专用于无毛皮肤感觉的神经元，部分反映了支配这些皮肤区域的机械感受器的高密度。

附：英文原文

Title: Mechanoreceptor synapses in the brainstem shape the central representation of touch

Author: Brendan P. Lehnert, Celine Santiago, Erica L. Huey, Alan J. Emanuel, Sophia Renauld, Nusrat Africawala, Ilayda Alkislar, Yang Zheng, Ling Bai, Charalampia Koutsioumpa, Jennifer T. Hong, Alexandra R. Magee, Christopher D. Harvey, David D. Ginty

Issue&Volume: 2021-10-11

Abstract: Mammals use glabrous (hairless) skin of their hands and feet to navigate and manipulate their environment. Cortical maps of the body surface across species contain disproportionately large numbers of neurons dedicated to glabrous skin sensation, in part reflecting a higher density of mechanoreceptors that innervate these skin regions. Here, we find that disproportionate representation of glabrous skin emerges over postnatal development at the first synapse between peripheral mechanoreceptors and their central targets in the brainstem. Mechanoreceptor synapses undergo developmental refinement that depends on proximity of their terminals to glabrous skin, such that those innervating glabrous skin make synaptic connections that expand their central representation. In mice incapable of sensing gentle touch, mechanoreceptors innervating glabrous skin still make more powerful synapses in the brainstem. We propose that the skin region a mechanoreceptor innervates controls the developmental refinement of its central synapses to shape the representation of touch in the brain.

DOI: 10.1016/j.cell.2021.09.023

Source: https://www.cell.com/cell/fulltext/S0092-8674(21)01106-5