Effect of hypoxia and hypercapnia on catecholamine content in cat carotid body. J Appl Physiol Respir Environ Exerc Physiol 1983 May;54(5):1408-13
Date
05/01/1983Pubmed ID
6408049DOI
10.1152/jappl.1983.54.5.1408Scopus ID
2-s2.0-0020570226 (requires institutional sign-in at Scopus site) 31 CitationsAbstract
The purpose of this study was to determine the content of catecholamines (CA) in the cat carotid body before and after 0.5 h exposures to normoxic normocapnia [arterial O2 partial pressure (Pao2) 126 +/- 28 Torr, arterial CO2 partial pressure (Paco2) 36.4 +/- 1.5 Torr], hypoxic normocapnia (Pao2 25 +/- 3 Torr, Paco2 36.7 +/- 3.3 Torr), and normoxic hypercapnia (Pao2 132 +/- 13 Torr, Paco2 = 98.2 +/- 7.6 Torr). CA synthesis was blocked using alpha-methylparatyrosine methyl ester (AMPT) prior to alterations in the inspired air. There was a significant decrease in carotid body content of dopamine (DA), norepinephrine (NE), and epinephrine (E) 1 h after AMPT administration. Analysis of variance and Duncan new multiple range procedures revealed that during the subsequent 0.5-h exposures to normoxia, hypoxia, or hypercapnia, only the decrease in DA during hypoxia was significantly greater than that during normoxia; the loss during hypercapnia was not. The decreases in NE during the three exposures were indistinguishable among themselves as were the decreases in E. The decrease in CA content is probably attributable to increased release. The data reveal that the release of CAs during the chemoreception of hypoxia is different from that during the chemoreception of hypercapnia and support the concept of different mechanisms for the chemoreception of hypoxia and hypercapnia.
Author List
Fitzgerald RS, Garger P, Hauer MC, Raff H, Fechter LAuthor
Hershel Raff PhD Professor in the Academic Affairs department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCarbon Dioxide
Carotid Body
Catecholamines
Cats
Dopamine
Epinephrine
Female
Male
Methyltyrosines
Norepinephrine
Oxygen