MEDULLARY RESPIRATORY NEURONAL-ACTIVITY MODULATED BY STIMULATION OF THE FASTIGIAL NUCLEUS OF THE CEREBELLUM

Authors
Citation
F. Xu et Dt. Frazier, MEDULLARY RESPIRATORY NEURONAL-ACTIVITY MODULATED BY STIMULATION OF THE FASTIGIAL NUCLEUS OF THE CEREBELLUM, Brain research, 705(1-2), 1995, pp. 53-64
Citations number
27
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences
Journal title
Brain research → ACNP
ISSN journal
0006-8993
Volume
705
Issue
1-2
Year of publication
1995
Pages
53 - 64
Database
ISI
SICI code
0006-8993(1995)705:1-2<53:MRNMBS>2.0.ZU;2-N
Abstract
The ability of the rostral fastigial nucleus (FNr) of the cerebellum t o modulate medullary respiratory neuronal activity was examined in 17 anesthetized, paralyzed and ventilated cats. A bipolar stimulating ele ctrode was positioned into the FNr and tungsten microelectrodes used t o record units within the nucleus tractus solitarius (NTS), nucleus am biguus (NA) and nucleus retroambigualis (NRA). Transient stimuli(< 150 mu A, 5-200 Hz) were delivered during inspiration or expiration, and the effects noted on medullary neuronal activity and the phrenic neuro gram. The results showed that FNr stimulation: (1) modulated inspirato ry and expiratory neuronal (ramp-, early- and late-inspiratory and sta ge I and II expiratory) discharges recorded from the NTS, NA and NRA ( n = 67, 14 and 28) when stimuli(greater than or equal to 20-50 Hz) wer e delivered during either the inspiratory or expiratory phases; (2) te rminated the burst durations of inspiratory (77%) and expiratory (94%) neurons with stimulus-response latencies of 28.2 +/- 3.1 ms (inspirat ory) and 29.4 +/- 3.6 ms (expiratory); (3) elicited changes in phrenic neurogram concomitant with the effects noted on medullary neuronal ac tivities; (4) failed to change heart rate and arterial blood pressure; and (5) did not affect medullary neuronal and phrenic nerve activity following kainic acid injection into the FNr. We conclude that activat ion of the FNr (likely its cell bodies) can modulate the respiratory o utput via influences on medullary respiratory-related neurons. The pri mary cerebellar effect across all sub-types of respiratory neurons was early termination.