Inhibitory influences on hypoglossal neural activity by stimulation of midpontine dorsal tegmentum in decerebrate cat.
In the spontaneously breathing decerebrate cat, the properties of the suppressive effects on hypoglossal nerve activity and on diaphragmatic activity elicited by stimulation of the midpontine dorsal tegmentum (DTF area) were analyzed. Stimulation simultaneously decreased the activities of the hypoglossal nerve as well as that of the diaphragm. However, the inhibitory influences on the above two kinds of activities were different in nature. Diaphragmatic activity, once suppressed by stimulation, recovered and gradually became greater in amplitude in spite of the continuation of stimulation. In contrast, DTF stimulation depressed tonic discharges of the hypoglossal nerve, and the decreased tonic nerve activity persisted after stimulation ended. Rhythmic hypoglossal activity, once suppressed by stimulation, reappeared during DTF stimulation. Such a rhythmic activity, however, vanished after the termination of stimulation, although the rhythmic diaphragmatic activity did not.
Kawahara
K
K
Department of Information Engineering, Yamagata University, Yonezawa, Japan.
Nakazono
Y
Y
Kumagai
S
S
Yamauchi
Y
Y
Miyamoto
Y
Y
D000200:Action Potentials; D000818:Animals; D002415:Cats; D003655:Decerebrate State / Q000503:physiopathology*; D003964:Diaphragm / Q000294:innervation* / Q000502:physiology; D004558:Electric Stimulation; D007002:Hypoglossal Nerve / Q000502:physiology*; D009433:Neural Inhibition; D009434:Neural Pathways / Q000502:physiology; D011149:Pons / Q000502:physiology*