CMAP & MUNE (Motor)

A compound muscle action potential (CMAP) is a crucial measurement used in the study of diseases affecting the neuromuscular system. CMAP represents the summed electrical response generated by a group of muscle fibers in response to peripheral nerve stimulation.

CMAP provides an assessment of the total excitability from a particular muscle or muscle group. Alterations in CMAP characteristics, such as amplitude and latency, provide valuable insights into the pathological processes affecting neuromuscular connectivity and function in rodent model of neurological diseases, such as amyotrophic lateral sclerosis (ALS).

Motor Unit Number Estimation (MUNE) is a technique used to assess the number of functioning motor units within a muscle. Motor units consist of a motor neuron and the muscle fibers that it innervates. In this technique, sub-maximal stimulations of a peripheral nerve are used to obtain an average single motor unit potential (SMUP) amplitude, which represents the number of muscle fibers innervated by a single motor neuron.

MUNE can sensitively identify and track motor unit loss. In the context of neurodegenerative diseases affecting the neuromuscular system, such as amyotrophic lateral sclerosis (ALS), MUNE is employed to evaluate the loss of motor neurons and subsequent denervation of muscle fibers. A decline in MUNE indicates the loss of motor units, reflecting the progression of neurodegenerative processes affecting motor neurons.