Low-Intensity Focused Ultrasound Alleviates Spasticity and Increases Expression of the Neuronal K-Cl Cotransporter in the L4-L5 Sections of Rats Following Spinal Cord Injury

• Published in: Frontiers in cellular neuroscience Vol. 16; p. 882127
• Main Authors: Liao, Ye-Hui, Chen, Mo-Xian, Chen, Shao-Chun, Luo, Kai-Xuan, Wang, Bing, Ao, Li-Juan, Liu, Yao
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 12-05-2022; Frontiers Media S.A
• Subjects: Animals; Cellular Neuroscience; Electromyography; Frequency dependence; Immunofluorescence; KCC2; low-intensity focused ultrasound; Medical research; Muscle contraction; Muscle pain; Nervous system; neurocircuits; Neurons; Pathogenesis; Potassium-chloride cotransporter; Spasticity; Spinal cord injuries; spinal cord injury; Ultrasonic imaging; Ultrasound; Urination; China; spinal cord injury; low-intensity focused ultrasound; spasticity; neurocircuits; KCC2
• ISSN: 1662-5102; 1662-5102
• DOI: 10.3389/fncel.2022.882127

Low-intensity focused ultrasound (LIFU) has been shown to provide effective activation of the spinal cord neurocircuits. The aim of this study was to investigate the effects of LIFU in order to alleviate spasticity following spinal cord injury (SCI) by activating the spinal neurocircuits and increasing the expression of the neuronal K-Cl cotransporter KCC
. Adult male Sprague Dawley (SD) rats (220-300 g) were randomly divided into a sham control group, a LIFU
group, and a LIFU
group. The mechanical threshold hold (g) was used to evaluate the behavioral characteristics of spasm. Electromyography (EMG) was used to assess activation of the spinal cord neurocircuits and muscle spontaneous contraction. Spasticity was assessed by frequency-dependent depression (FDD). The expression of KCC
of the lumbar spinal cord was determined via western blot (WB) and immunofluorescence (IF) staining. The spinal cord neurocircuits were activated by LIFU simulation, which significantly reduced the mechanical threshold (g), FDD, and EMG recordings (s) after 4 weeks of treatment. WB and IF staining both demonstrated that the expression of KCC
was reduced in the LIFU
group (
< 0.05). After 4 weeks of LIFU stimulation, expression of KCC
had significantly increased (
< 0.05) in the LIFU
group compared with the LIFU
group. Thus, we hypothesized that LIFU treatment can alleviate spasticity effectively and upregulate the expression of KCC
in the L4-L5 section of SCI rats.