Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation

Producción Científica

Detalles Bibliográficos
Autores: Rigual Bonastre, Ricardo Jaime, González, E., González Martínez, Constancio, Fidone, Salvatore
Tipo de recurso: artículo
Fecha de publicación:1986
País:España
Institución:Universidad de Valladolid
Repositorio:UVaDOC. Repositorio Documental de la Universidad de Valladolid
OAI Identifier:oai:uvadoc.uva.es:10324/6844
Acceso en línea:https://doi.org/10.1016/0006-8993(86)90398-7
http://uvadoc.uva.es/handle/10324/6844
Access Level:acceso abierto
Palabra clave:Neurofisiología
id ES_3825eeebf63c5a3ce9cc32eb8d65a308
oai_identifier_str oai:uvadoc.uva.es:10324/6844
network_acronym_str ES
network_name_str España
repository_id_str
spelling Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic StimulationRigual Bonastre, Ricardo JaimeGonzález, E.González Martínez, ConstancioFidone, SalvatoreNeurofisiologíaProducción CientíficaThe role of catecholamines (CAs) in cat carotid body chemoreception has been controversial. On the basis of pharmacological experiments, it would appear that endogenous dopamine (DA) may act either as an inhibitory or excitatory transmitter. Neurochemical studies on the effects of natural stimulation on the release of carotid body CAs in the cat have also been inconclusive. In the present study, we have characterized the synthesis and release of CAs in the in vitro cat carotid body preparation in response to different levels of hypoxic stimulation and have correlated these measures with the chemosensory activity of the carotid sinus nerve. The synthesis of [3H]DA and [3H]norepinephrine was linear for at least 4 h in carotid bodies incubated with their natural precursor [~H]tyrosine. Synthesis of both [3H]CAs plateaued when the [3H]tyrosine concentration in the media reached 40 uM, which is a concentration similar to that found in cat plasma. Exposure of the animals to an atmosphere of 10% 02 in N~ for 3 h prior to removal and incubation of the carotid bodies with [3H]tyrosine resulted in an approximately 100% increase in the rate of [3H]DA synthesis but no change in [3H]norepinephrine synthesis. This selective increase in [3H]DA synthesis was not detected when [3H]dihydroxyphenylalanine was used as precursor. Carotid bodies first incubated with [3H]tyrosine and later superfused with solutions equilibrated with different gas mixtures (0 100% 0 2 in N2) exhibited an increase in [3H]DA release and carotid sinus nerve discharge which were inversely related to the oxygen concentration. This relationship was strongest for the weaker stimuli (between 50% and 20% O 2 in N2), where both nerve activity and [3H]DA release increased almost in parallel. With lower oxygen concentrations (10% O 2 and 0% 02 equilibrated solutions), the increase in the release of [3H]DA was proportionally greater than the increase in carotid sinus nerve discharge. Our results demonstrate that hypoxic stimulation increases both the rate of synthesis and release of DA in the cat carotid body. Although the precise role of DA in this chemoreceptor organ is presently unknown, our findings suggest that this biogenic amine plays a direct role in generating or controlling the electrical activity in the carotid sinus nerve. INTRODUCTION The mammalian carotid body is an arterial chemoreceptor organ activated by low paO2, low pH and high p~CO2 (ref. 21). Structurally, the receptor complex is formed by clusters of two types of cells, the type I and type II cells; the clusters lie within a supporting connective tissue matrix containing a dense capillary net24, 41. Sensory fibers of the carotid sinus nerve (CSN) penetrate these cell clusters to end in synaptic apposition with type I cells, which are considered to be preneural (receptor) elements. Two perennial issues pertaining to arterial chemoreception, concern first, whether the type 1 cells are in factElsevier1986info:eu-repo/semantics/articleapplication/pdfhttps://doi.org/10.1016/0006-8993(86)90398-7http://uvadoc.uva.es/handle/10324/6844reponame:UVaDOC. Repositorio Documental de la Universidad de Valladolidinstname:Universidad de ValladolidInglésinfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-nd/4.0/oai:uvadoc.uva.es:10324/68442026-06-13T12:44:47Z
dc.title.none.fl_str_mv Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
title Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
spellingShingle Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
Rigual Bonastre, Ricardo Jaime
Neurofisiología
title_short Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
title_full Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
title_fullStr Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
title_full_unstemmed Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
title_sort Synthesis and Release of Catecholamines by the Cat Carotid Body in Vitro: Effects of Hypoxic Stimulation
dc.creator.none.fl_str_mv Rigual Bonastre, Ricardo Jaime
González, E.
González Martínez, Constancio
Fidone, Salvatore
author Rigual Bonastre, Ricardo Jaime
author_facet Rigual Bonastre, Ricardo Jaime
González, E.
González Martínez, Constancio
Fidone, Salvatore
author_role author
author2 González, E.
González Martínez, Constancio
Fidone, Salvatore
author2_role author
author
author
dc.subject.none.fl_str_mv Neurofisiología
topic Neurofisiología
description Producción Científica
publishDate 1986
dc.date.none.fl_str_mv 1986
dc.type.none.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv https://doi.org/10.1016/0006-8993(86)90398-7
http://uvadoc.uva.es/handle/10324/6844
url https://doi.org/10.1016/0006-8993(86)90398-7
http://uvadoc.uva.es/handle/10324/6844
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-nd/4.0/
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Elsevier
publisher.none.fl_str_mv Elsevier
dc.source.none.fl_str_mv reponame:UVaDOC. Repositorio Documental de la Universidad de Valladolid
instname:Universidad de Valladolid
instname_str Universidad de Valladolid
reponame_str UVaDOC. Repositorio Documental de la Universidad de Valladolid
collection UVaDOC. Repositorio Documental de la Universidad de Valladolid
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869406082288320512
score 15.300719

Similares en LA Referencia