Accession Number : ADA116658

Title :   Ventilatory Responsiveness of Goats with Ablated Carotid Bodies,


Personal Author(s) : Steinbrook,R A ; Donovan,J C ; Gabel,R A ; Leith,D E ; Fencl,Vladimir

PDF Url : ADA116658

Report Date : 03 Jun 1982

Pagination or Media Count : 33

Abstract : We studied the effect of ablating the carotid bodies (CBx) on resting pulmonary ventilation of awake goats, on composition of their arterial blood and CSF, and on responses to respiratory stimuli (hypercapnia, hypoxia, injection of cyanide). Hyperventilation in response to acute hypoxia was abolished. The ventilatory response to injection of cyanide was markedly diminshed but not completely abolished after CBx; onset of the response was delayed and the interaction of cyanide and hypoxia appeared eliminated. Resting pulmonary ventilation was reduced by almost one fifth, and PaCO2 was increased following CBx. In CSF, pH and PCO2 were not different before and after CBx, suggesting that the stimulus for the central chemoreceptor was not diminshed. The difference in PCO2 between arterial blood and CSF was reduced after CBx. In spite of the resting hypercapnia after CBx, the goats responded to hyperoxic CO2 rebreathing with a similar increase in ventilation before and after CBx. We conclude that the carotid bodies contribute significantly to the resting respiratory drive in normoxic goats. The increase in ventilation in response to acute hypercapnia appears to be mediated by the central chemoreceptors. (Author)

Descriptors :   *Respiration, *Pulmonary function, Goats, Carbon dioxide, Arteries, Blood analysis, Hypoxia, Physiological effects, Cyanides, Chemoreceptors

Subject Categories : Anatomy and Physiology
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE