Transcranial Direct Current Stimulation (tDCS) Induces Analgesia in Rats with Neuropathic Pain and Alcohol Abstinence

Abstract

Neuromodulatory techniques have been studied to treat drug addiction or compulsive eating as well as different chronic pain conditions, such as neuropathic and inflammatory pain in the clinical and preclinical settings. In this study, we aimed to investigate the effect of transcranial direct current stimulation (tDCS) on the association of alcohol withdrawal with neuropathic pain based on nociceptive and neurochemical parameters in rats. Thirty-six adult male Wistar rats were randomized into five groups: control, neuropathic pain, neuropathic pain + tDCS, neuropathic pain + alcohol, and neuropathic pain + alcohol + tDCS. The neuropathic pain model was induced by chronic constriction injury (CCI) to the sciatic nerve. Rats were then exposed to alcohol (20%) by oral gavage administration for 15 days (beginning 24 h after CCI). tDCS was started on the 17th day after surgery and lasted for 8 consecutive days. The nociceptive test (hot plate) was performed at baseline, 16 days after CCI, and immediately and 24 h after the last session of tDCS. Rats were killed by decapitation, and structures were removed and frozen for biochemical analysis (nerve growth factor and interleukin (IL-1α, IL-1β, and IL-10 measurements). Neuropathy-induced thermal hyperalgesia was reversed by tDCS, an effect that was delayed by alcohol abstinence. In addition, tDCS treatment induced modulation of central levels of IL-1α, IL-1ß, and IL-10 and neurotrophic growth factor. We cannot rule out that the antinociceptive effect of tDCS could be related to increased central levels of IL-1α and IL-10. Therefore, tDCS may be a promising non-pharmacological therapeutic approach for chronic pain treatment.

Mechanisms of transcranial direct current stimulation (tDCS) for pain in patients with fibromyalgia syndrome

“…Animal models show that tDCS can change neuroinflammatory mediators. IL-1β (Lopes et al, 2020;Regner et al, 2020) and IL-6 (Guo et al, 2020) were reduced in the CNS structure of animals following tDCS stimulation, while IL-1α (Santos et al, 2020), IL-10 (Santos et al, 2020), andIL-4 (Lopes et al, 2019) were increased. Moreover, animals in these experiments showed analgesic response after tDCS stimulation, which provided a window into the pain relief caused by neuroinflammatory modulation.…”

Transcranial direct current stimulation-mediated miR-298-5p downregulation enhances autophagy by targeting LC3 to promote motor recovery after spinal cord injury

“…The cathode electrode was placed over the supraorbital area (midpoint between the lateral angles of both eyes) [39]. The rats were restrained by a soft cloth during stimulation [40,41] (Fig. 2).…”

Animal Experiments Used in Experimental Neuroscience Research: Learning, Memory, Anxiety, Depression and Motor Function Behavioural Experiments

“…Animals are placed into glass funnels on the heated surface and the time between the rat's placement and the first response (foot licking, jumping, or rapid raising of the paws) is recorded as the paw withdrawal latency. The The hind paw retraction time (sec) is measured for each animal (20).…”