[Interaction of thermoreceptive and vestibular signalling in regulating the activity of flexor and extensor motor nuclei during cold tremor].

The impulse activity of flexor and extensor gamma- and alpha-motoneurons was investigated in anesthetized cats during cold tremor. Total cooling, local cold stimulation of thermoreceptors or electrical stimulation of dorsomedial area of posterior hypothalamus were shown to evoke primary activation of flexor--and simultaneous inhibition of extensor gamma-motoneurons, with secondary activation of flexor alpha-motoneurons. Caloric stimulation of the vestibular receptors during cold tremor evokes primary inhibition of the activity of flexor alpha-motoneurons and secondary inhibition of flexor gamma-motoneurons as well as simultaneous activation of extensor gamma-motoneurons.