Recording of motor and somatosensory evoked potential in an anaesthetised Wistar rat using digital polyrite system

Abstract

The aim of this article is to explain the detailed methodology to record Motor evoked potential (MEP) and somatosensory evoked potential (SSEP) in adult albino Wistar rat, male (200–250 g) which has not been defined previously. We have standardised recording of both MEP and SSEP in these rats under anaesthesia on ADI digital polyrite system. Evoked potentials have been widely studied in spinal cord injured patients to estimate the degree of injury and to establish a predictive measure of functional recovery. MEPs and SSEPs, arising from the motor cortex or peripheral nerve and generated either by direct electrical stimulation or by transcranial magnetic stimulation, have been advocated as a reliable indicator of descending and ascending pathway integrity. In the rat brain, there is a physical overlap between the motor and somatosensory cortex. Hence, our objective was to identify the exact area for stimulation in the cortex where we could record maximum response with the application of minimum electrical stimulation. The recording of MEP and SSEP together provides a powerful neurological technique to monitor the tracts of the spinal cord.