Linked Life Data

2887477

Source:http://linkedlifedata.com/resource/pubmed/id/2887477

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-10-19
pubmed:abstractText
The sympathetic neuroeffector system in the mammalian cerebral circulation has a number of distinctive features that reflect its specialized role in this vascular bed: 1) there is limited alpha-adrenoceptor-mediated contraction in large vessels that becomes progressively less important with branching; 2) contraction is limited by receptor number; small branches often seem to have no functional alpha adrenoceptors; 3) adrenoceptor affinity for norepinephrine is low and so is sensitivity; and 4) the dominant alpha-adrenoceptor subtype differs in different species and may have unique characteristics in some. There is a mechanism of non-alpha-adrenoceptor-mediated contraction involving low-affinity receptor sites--extraceptors--activated by sympathetic nerves. The pig has a seemingly atypical sympathetic mechanism. On the basis of current information the sympathetic neuroeffector mechanisms of the rabbit seem most clearly related to the human. The size, pattern, and distribution of sympathetic control suggest that the role of the sympathetic nerves is to protect the smaller pial arteries against the consequences of sudden increases in sympathetic adrenal discharge. It is not an important mechanism of controlling cerebral blood flow.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0892-6638
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
193-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Sympathetic control of cerebral arteries: specialization in receptor type, reserve, affinity, and distribution.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.