经颅聚焦超声刺激导水管周围灰质用于镇痛。

Transcranial Focused Ultrasound Stimulation of Periaqueductal Gray for Analgesia.

出版信息

IEEE Trans Biomed Eng. 2022 Oct;69(10):3155-3162. doi: 10.1109/TBME.2022.3162073. Epub 2022 Sep 19.

DOI:10.1109/TBME.2022.3162073

Abstract

OBJECTIVE

Transcranial focused ultrasound (tFUS) is regarded as a promising non-invasive stimulation tool for modulating brain circuits. The aim of this study is to explore the feasibility of tFUS stimulation for analgesia applications.

METHODS

50 µl of 3% formalin solution was injected into the rat's left hindpaw to build a pain model, and then the local field potential (LFP) activities of the dorsal horn were tracked after a recording electrode was placed in the spinal cord. Rats were randomly divided into two groups: control group and tFUS group. At the 30 minute after formalin injection, tFUS (US-650 kHz, PD = 1 ms, PRF = 100 Hz, 691 mW/cm) was conducted to stimulate the periaqueductal gray (PAG) for 5 minutes (on 5 s and off 5 s) in the tFUS group, but there was no treatment in the control group. In addition, the analgesia mechanism (LFP recording from the PAG) and safety assessment (histology analysis) were carried out.

RESULTS

The tFUS stimulation of the PAG can suppress effectively the nociceptive activity generated by formalin. The findings of the underlying mechanism exploration indicated that the tFUS stimulation was able to activate the PAG directly without causing notable temperature change and tissue injury.

CONCLUSION

The results illustrated that the tFUS stimulation of the PAG can achieve the effect of analgesia.

SIGNIFICANCE

This work provides new insights into the development of non-invasive analgesic technology in the future.

摘要

目的

经颅聚焦超声（tFUS）被认为是一种有前途的非侵入性刺激工具，可用于调节大脑回路。本研究旨在探讨 tFUS 刺激用于镇痛应用的可行性。

方法

将 50 μl 3%甲醛溶液注入大鼠左后爪以建立疼痛模型，然后在脊髓中放置记录电极后跟踪背角的局部场电位（LFP）活动。大鼠随机分为两组：对照组和 tFUS 组。在甲醛注射后 30 分钟，tFUS（US-650 kHz，PD=1 ms，PRF=100 Hz，691 mW/cm）用于刺激 tFUS 组的导水管周围灰质（PAG）5 分钟（开 5 秒，关 5 秒），但对照组没有治疗。此外，还进行了镇痛机制（来自 PAG 的 LFP 记录）和安全性评估（组织学分析）。