Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA.
Science. 2024 Nov 8;386(6722):686-692. doi: 10.1126/science.adq8834. Epub 2024 Nov 7.
Many hairy mammals perform rapid oscillations of their body, called wet dog shakes, to remove water and irritants from their back hairy skin. The somatosensory mechanisms that underlie this behavior are unclear. We report that Piezo2-dependent mechanosensation mediates wet dog shakes evoked by water or oil droplets applied to back hairy skin of mice. Unmyelinated C-fiber low-threshold mechanoreceptors (C-LTMRs) were activated by oil droplets, and their optogenetic activation elicited wet dog shakes. Ablation of C-LTMRs attenuated this behavior. Moreover, C-LTMRs synaptically couple to spinoparabrachial neurons, and optogenetically inhibiting spinoparabrachial neuron synapses and excitatory neurons in the parabrachial nucleus impaired both oil droplet- and C-LTMR-evoked wet dog shakes. Thus, a C-LTMR-spinoparabrachial pathway promotes wet dog shakes for removal of water and mechanical irritants from back hairy skin.
许多多毛哺乳动物会快速抖动身体，即所谓的“甩干”，从而清除背部毛发上的水分和刺激物。但目前尚不清楚这一行为背后的躯体感觉机制。我们的研究表明，机械敏感蛋白 Piezo2 介导了水或油滴作用于小鼠背部毛发时引发的“甩干”行为。油滴会激活无髓鞘 C 纤维低阈值机械感受器（C-LTMRs），而其光遗传学激活则可引发“甩干”行为。C-LTMR 消融则可减弱该行为。此外，C-LTMRs 与脊髓-臂旁核神经元形成突触连接，光遗传学抑制脊髓-臂旁核神经元突触和臂旁核内兴奋性神经元均可损害油滴和 C-LTMR 引发的“甩干”行为。因此，C-LTMR-脊髓-臂旁核通路促进了“甩干”行为，从而清除背部毛发上的水分和机械性刺激物。
