Changes in mono- and polysynaptic spinal reflexes in the presence of a peripheral inflammatory process

Summary

An inflammatory process developing on the extremity caused changes in the mono- and polysynaptic reflexes. Monosynaptic reflexes of the flexor centers were enhanced, those of the extensor centers — decreased. Less distinct changes were established in respect of polysynaptic reflexes. These changes may probably be explained by the fact that impulsation from the inflammatory focus spread along of fibers groups III–IV and causes a partial neuron depolarization of the flexor centers and neuron hyperpolarization of extensor centers, as a result of which the test stimulation involves a greater or lesser number of neurons in the reaction. The changes in the reflex reactions of diseased organs conditioned by this mechanism — excessive intensification or, on the contrary, marked depression.

Of special significance is the fact that regular changes in the mono- and polysynaptic reflexes occur only on the 3rd–4th day after the development of inflammation, whereas functional disturbance of the limb flexion occurs during the first hour after the injury of the paw. Late changes in the mono- and polysynaptic reflexes followed a number of other interventions: deafferentation, tenotomy etc., which also caused immediate functional disturbances.

Evidently function disturbances in these experiments, at least at the early stages, are the result of complex activity of the nervous system, going beyond the spinal segment.