Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-2
pubmed:abstractText
Subcellular regulation mechanisms of calcium concentrations related to oxygen sensing in the carotid body are unclear. In the present study, we investigated the ultrastructural distribution patterns of calcium in carotid body cells and its changes evoked by hypoxia. Carotid bodies were dissected from anesthetized cats exposed in vivo to normoxic or acute hypoxic conditions. We used the oxalate-pyroantimonate technique that yields an electron-opaque calcium precipitate. X-ray microanalysis and appropriate controls confirmed the presence of calcium in the precipitate. Calcium precipitates were found in all types of cells in carotid body parenchyma: chemoreceptor cells, sustentacular cells, and nerve endings. In normoxic chemoreceptor cells, the precipitate was localized in dense core vesicles, mitochondria, and nuclei, but rarely in the cytoplasm. The most apparent effect of hypoxia was disappearance of the precipitate from dense core vesicles and was associated with its appearance in the cytoplasm. The amount of precipitate throughout the carotid body parenchyma was decreased overall due to hypoxia. These results indicate the involvement of subcellular calcium trafficking in hypoxia-sensing in the carotid body. The redistribution pattern of granular calcium deposits from organelles to the cytoplasm of chemoreceptor cells agrees with biochemical data of calcium release from intracellular stores during hypoxia.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0065-1281
pubmed:author
pubmed:issnType
Print
pubmed:volume
103
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
305-13
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Calcium handling by the cat carotid body--a pyroantimonate study.
pubmed:affiliation
Department of Neurophysiology, Medical Research Center, Warsaw, Poland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't