Faculty Collaboration Database

The cerebellar fastigial nucleus contributes to CO2-H+ ventilatory sensitivity in awake goats. Respir Physiol Neurobiol 2007 Aug 01;157(2-3):242-51

Date

03/06/2007

Pubmed ID

17336598

Pubmed Central ID

PMC1994784

DOI

10.1016/j.resp.2007.01.019

Scopus ID

2-s2.0-34248644852 (requires institutional sign-in at Scopus site)   28 Citations

Abstract

The purpose of this study was to test the hypothesis that an intact cerebellar fastigial nucleus (CFN) is an important determinant of CO(2)-H(+) sensitivity during wakefulness. Bilateral, stainless steel microtubules were implanted into the CFN (N=9) for injection (0.5-10 microl) of the neurotoxin ibotenic acid. Two or more weeks after implantation of the microtubules, eupneic breathing and CO(2)-H(+) sensitivity did not differ significantly (P>0.10) from pre-implantation conditions. Injection of ibotenic acid (50 mM) did not significantly alter eupneic Pa(CO2) (P>0.10). The coefficient of variation of eupneic Pa(CO2) was 4.0+/-0.6 and 3.7+/-0.4% over the 2 weeks before and after the lesion, respectively. CO(2)-H(+) sensitivity expressed as inspired ventilation/Pa(CO2) decreased from 2.15+/-0.17 pre-lesion to 1.58+/-0.26 l/(min mmHg) 3-6 days post-lesion (P<0.02, -27%). There was no significant (P>0.10) recovery of sensitivity between 7 and 10 days post-lesion. The lesion also increased (P<0.05) the day-to-day variability of this index by nearly 100%. When CO(2) sensitivity was expressed as elevated inspired CO(2)/room air V (I), values at 7%, but not 3 and 5% inspired CO(2), were reduced and more variable (P<0.05) after the ibotenic acid injections. We conclude that during wakefulness, the CFN contributes relatively more to overall ventilatory drive at high relative to low levels of hypercapnia.

Author List

Martino PF, Davis S, Opansky C, Krause K, Bonis JM, Pan LG, Qian B, Forster HV

Author

Hubert V. Forster PhD Professor in the Physiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Analysis of Variance
Animals
Blood Pressure
Carbon Dioxide
Cerebellar Nuclei
Excitatory Amino Acid Agonists
Female
Goats
Hydrogen
Ibotenic Acid
Male
Pulmonary Gas Exchange
Respiratory Mechanics
Wakefulness