Document Detail

Failure of pulmonary acidosis to increase respiratory drive.
MedLine Citation:
PMID:  1399996     Owner:  NLM     Status:  MEDLINE    
Experiments were performed to determine whether increases in acidity isolated to the pulmonary circulation would stimulate hypothesized pulmonary chemoreceptors and increase respiratory drive in the anesthetized paralyzed mechanically ventilated cat (n = 9). Respiratory drive was assessed by measuring the frequency and amplitude of the integrated phrenic neurogram. To create an isolated pulmonary acidosis, blood returning to the lung was acidified by infusion of 0.3 M lactic acid (1.91 ml/min) into the inferior vena cava, while systemic arterial pH was restored to near normal levels by simultaneous infusion of base (0.3 M NaOH) into the left atrium. Six minutes after the start of this dual infusion of acid and base, right ventricular (pulmonary) pH decreased from 7.286 to 7.179 and PCO2 increased 7 Torr. Systemic arterial pH and PCO2 were unchanged from measurements immediately before the infusion. This level of pulmonary acidosis failed to increase respiratory drive as assessed by phrenic activity. To test the sensitivity of the preparation to known systemic arterial chemical stimuli, a combined pulmonary and systemic acidosis was elicited by infusion of 0.3 M lactic acid into the inferior vena cava and 0.3 M NaCl into the left atrium. This infusion significantly lowered both systemic arterial and pulmonary arterial pH (7.343 to 7.155 for systemic arterial pH and 7.286 to 7.067 for pulmonary pH) and increased phrenic efferent activity 45%. We conclude that phrenic efferent activity is unaffected by moderate reductions in the pH of the pulmonary circulation in the absence of a significant systemic arterial acidosis.(ABSTRACT TRUNCATED AT 250 WORDS)
J A Orr; J A Carrithers; F Liu; H W Shirer
Related Documents :
12079056 - Intravenous micro-particle injection and pulmonary hypertension in broiler chickens: ca...
16179896 - Pulmonary arterial hypertension: pathobiology, diagnosis and treatment.
7249546 - A method for assessing responses of small arteries in man: effect of physiological and ...
19017876 - Genetic associations with hypoxemia and pulmonary arterial pressure in copd.
23555446 - Fibromuscular dysplasia of the lower extremities.
9059846 - The action of atp on the hepatic arterial and portal venous vascular networks of the ra...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  73     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1992 Aug 
Date Detail:
Created Date:  1992-11-12     Completed Date:  1992-11-12     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  672-8     Citation Subset:  IM    
Department of Physiology and Cell Biology, University of Kansas, Lawrence 66045.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Acidosis, Respiratory / physiopathology*
Blood Gas Analysis
Chemoreceptor Cells / physiology
Lactates / administration & dosage,  pharmacology
Lactic Acid
Phrenic Nerve / physiology
Pulmonary Circulation / physiology
Respiration / physiology*
Respiration, Artificial
Reg. No./Substance:
0/Lactates; 50-21-5/Lactic Acid

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Short-duration spaceflight impairs human carotid baroreceptor-cardiac reflex responses.
Next Document:  PEEP is necessary for exogenous surfactant to reduce pulmonary edema in canine aspiration pneumoniti...