Premium
An Inact Cerebellar Fastigial Nucleus (CFN) is an Important Determinant of CO2 Sensitivity in Awake Goats
Author(s) -
Martino Paul Frank,
Davis S,
Opansky C,
Pan L G,
Krause K,
Qian B,
Bonis J M,
Forster H V
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a786-b
Subject(s) - ibotenic acid , tidal volume , ventilation (architecture) , heart rate , fastigial nucleus , microdialysis , anesthesia , respiratory rate , acidosis , medicine , blood pressure , chemistry , zoology , respiratory system , biology , cerebellum , central nervous system , engineering , mechanical engineering
We previously reported that in goats with chronically implanted stainless steel microtubules, microdialysis induced focal acidosis in the rostral CFN (rCFN) and caudal CFN (cCFN) increased and decreased pulmonary ventilation (V I ), respectively. Here we report that injection of 10ul (n=8) ibotenic acid into the rCFN significantly (P < 0.05) increased both V I (36.1% ± 0.11) and breathing frequency (f) (42% ± 0.3) up to one hour after injection, with no significant effects on tidal volume (V T ), mean arterial blood pressure (MABP) or heart rate (HR). 10ul (n=5) ibotenic acid injections into the cCFN did not significantly change V I , f, V T , MABP, or HR up to one hour after injection. However, in all goats, there were balance and posture deficits between 3 to 24 hours after injection. Histology indicated that in all goats portions of both the rCFN and cCFN were lesioned. These lesions did not significantly alter resting PaCO 2 , but decreased (P < 0.02) whole body CO 2 sensitivity by 17%. In contrast, in two goats where the lesions were outside the CFN there was an average increase in the CO 2 sensitivity of 52.5% ± 4.5. These data indicate that an intact CFN is an important determinant of CO 2 sensitivity and that the rCFN and cCFN have both common and unique contributions to physiological functions. Supported by NIH HL‐25739 and by the Department of Veterans Affairs.