[Changes in segmental reflexes upon stimulation of the locus coeruleus of the brain stem and potentiation of catecholamine action].

Rhythmic stimulation of locus coeruleus was accompanied by a depressed inhibitory action of flexor reflex afferents and recurrent inhibition on extensor motoneurons in anaesthetized and decerebellized cats. Such stimulation had no essential effect on the direct inhibition of extensor and flexor motoneurons, on the excitatory action of flexor reflex afferents and recurrent inhibition on the flexor motoneurons. The injection of pyrogallol caused similar effect but it was greatly diminished by cold blockage or transsection of the spinal cord. The experiments with partial cuts of the spinal cord to consider the effects as a result of activation of coerulo-spinal pathway which descend in the ventral quadrant of the spinal cord.