The Role of Synaptic Plasticity in Neuropathic Pain Treatment
Research type
Research Study
Full title
Treating neuropathic pain secondary to peripheral nerve injury with electrical stimulation – investigating a mechanistic role for Long Term Depression
IRAS ID
225619
Contact name
Andreas Goebel
Contact email
Duration of Study in the UK
1 years, 11 months, 30 days
Research summary
Summary of Research
To assist research and future treatments for chronic pain it is important to understand the mechanisms determining whether a pain becomes persistent and how this can potentially be reversed. Long lasting changes in the strength of connections in nerve pathways can occur. These include long-term potentiation (LTP) which enhances synaptic strength (strength of signal between nerve cells) and long-term depression (LTD) which reduces synaptic strength. It is thought that LTP in pain pathways may lead to persistent pain. This study will explore the underlying mechanisms that lead to the development of persistent pain following nerve injury and the mechanistic basis for a putative treatment. It will include participants, with one site of neuropathic pain, who have completed a previous study (EN-PENS). EN-PENS is a trial of the effectiveness of external non-invasive nerve stimulation. Study participants will attend a single investigative session lasting approximately 4hours. Participants will undergo sensory testing and electrical stimulation of the clinically-unaffected and affected limbs.The areas for this will depend on the site of their pain. On the unaffected side a test site will receive LTP induction followed by LTD. The affected site will be tested in the clinically affected zone. This will receive LTD induction. LTP and LTD will be induced by electrical stimulation of the skin using methods that have been used extensively in human studies. Quantitative measures of pain to single electrical pulses and mechanical stimuli (controlled pin prick stimulation, light touch) will be made. Qualitative measures of pain via a list of verbal descriptors will be made. The primary outcome measure for this study will be change in pain intensity of electrically evoked pain measures via a numerical rating scale. Other changes in pain intensity and pain and touch measures are included as secondary outcomes.
Summary of Results
The study provided evidence that treating nerve pain due to nerve injury with low frequency electrical stimulation of the skin is due to alterations in the strength of pain signalling in the spinal cord.REC name
North West - Liverpool Central Research Ethics Committee
REC reference
17/NW/0234
Date of REC Opinion
10 May 2017
REC opinion
Further Information Favourable Opinion