Department of Electrical Engineering & Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139.
Bioengineering Division, Draper, Cambridge, MA 02139.
Proc Natl Acad Sci U S A. 2022 Jun 7;119(23):e2117764119. doi: 10.1073/pnas.2117764119. Epub 2022 Jun 2.
Electrical nerve stimulation serves an expanding list of clinical applications, but it faces persistent challenges in selectively activating bundled nerve fibers. In this study, we investigated electrochemical modulation with an ion-selective membrane (ISM) and whether it, used together with electrical stimulation, may provide an approach for selective control of peripheral nerves. Guided by theoretical transport modeling and direct concentration measurements, we developed an implantable, multimodal ISM cuff capable of simultaneous electrical stimulation and focused Ca2+ depletion. Acutely implanting it on the sciatic nerve of a rat in vivo, we demonstrated that Ca2+ depletion could increase the sensitivity of the nerve to electrical stimulation. Furthermore, we found evidence that the effect of ion modulation would selectively influence functional components of the nerve, allowing selective activation by electrical current. Our results raise possibilities for improving functional selectivity of new and existing bioelectronic therapies, such as vagus nerve stimulation.
电神经刺激服务于越来越多的临床应用，但在选择性地激活束状神经纤维方面仍然面临挑战。在这项研究中，我们研究了带有离子选择性膜（ISM）的电化学调节，以及它是否与电刺激一起使用可能为选择性控制周围神经提供一种方法。在理论传输建模和直接浓度测量的指导下，我们开发了一种可植入的、多模态的 ISM 袖带，能够同时进行电刺激和聚焦 Ca2+耗竭。我们在体内急性植入大鼠坐骨神经上，并证明 Ca2+耗竭可以提高神经对电刺激的敏感性。此外，我们发现离子调制的效果会选择性地影响神经的功能成分，从而可以通过电流进行选择性激活。我们的结果为改善新的和现有的生物电子疗法（如迷走神经刺激）的功能选择性提供了可能性。
