Simultaneous Suppression of Postural Tone and Respiration and its Functional Significance in the Respiratory-Motor Coordination

Abstract

In acute precollicular-postmammillary decerebrate cats, stimulation of the dorsal part of the caudal tegmental field (DTF) in the pons along the midline results in long-lasting suppression of extensor muscle tone (Mori et al. 1982). During the course of our investigation on the coupling of the locomotor rhythm and the respiratory rhythm, we have recently found that DTF stimulation used for reducing the decerebrate rigidity not only elicits suppression of hindlimb extensor muscle tone but also suppresses respiratory movements (Kawahara et al. 1988b). Suppressed tonic discharges of the hindlimb antigravity muscles caused by DTF stimulation persist for more than several minutes after the stimulation ends. In contrast, respiratory movements, once markedly suppressed by DTF stimulation, gradually recover in spite of the continuation of the stimulation.