Evaluation of the Effect of the K+-Channel Opener Flupirtine on the Excitability of Human Peripheral Myelinated Axons in Vivo: a Randomised Controlled Trial
试验速览
- 阶段
- 1 期
- 状态
- 已完成
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Axonal Excitability as assessed with QTrac
研究概览
简要总结
Slow axonal Kv7 potassium channels are found along unmyelinated axons and at the nodes of Ranvier of myelinated axons in peripheral nerve. As such the pharmacological activation of Kv7 channels offers a potential means of reducing the excitability of peripheral axons. To determine whether this is the case for human peripheral myelinated axons, the effect of the Kv7 channel agonist flupirtine on the electrical excitability of A fibres was examined in both isolated segments of human sural nerve in vitro and in motor axons of the median nerve supplying abductor pollicus brevis in vivo. Axonal excitability was assessed in 21 human sural nerve fascicles in vitro and in 20 volunteers in vivo using threshold tracking in QTRAC (© Institute of Neurology, London, UK). Strength-duration time constant, rheobase current, relative refractory period (RRP), post spike superexcitability at 5 and 7 ms and threshold electrotonus over the 90 100 ms period were used as indices of electrical excitability. In addition, suppression of ectopic discharge in a model of upper limb ischaemia.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •voluntarily
- •age > 18 years old
排除标准
- •current use of medication (e.g. analgetics, antiepileptics, antidepressants, etc.)
- •prevailing organic disease (e.g. diabetes, vascular or neurologic illness, etc.)
- •previous physical trauma of the forearm (e.g. burning, surgery)
- •primary organ failure
- •pregnancy and lactation
研究组 & 干预措施
Placebo first
Volunteers receive placebo first and after a cross-over period of at least 7 days flupirtine second. On the days of the experiment outcome is taken as the change in excitability from Baseline (all measures before intervention) to a timepoint two hours after intervention
干预措施: flupirtine (Drug)
Flupirtine first
Volunteers receive flupirtine first and after a cross-over period of at least 7 days placebo second. On the days of the experiment outcome is taken as the change in excitability from Baseline (all measures before intervention) to a timepoint two hours after intervention
干预措施: flupirtine (Drug)
结局指标
主要结局
Axonal Excitability as assessed with QTrac
时间窗: Change of neuronal excitability from Baseline (before) to two hours after intervention
The primary outcome parameter of axonal excitability was the relative refractory period (RRP) as assessed with threshold tracking techniques. Strength-duration time constant, rheobase current, refractoriness determined at 2 and 2.5 ms, superexcitability at 7 ms and threshold electrotonus over the 90 100 ms period were used as secondary outcome measures.
次要结局
- Ectopic Discharge(Change of neuronal excitability from Baseline (before) to two hours after intervention)
研究者
Dr. Johannes Fleckenstein
Registrar, MD, Multidisciplinary Pain Centre, Department of Anaesthesiology
Ludwig-Maximilians - University of Munich