Linked Life Data

8897954

Source:http://linkedlifedata.com/resource/pubmed/id/8897954

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 2
pubmed:dateCreated
1996-12-16
pubmed:abstractText
Using the acute cranial window technique in rabbits under surgical anesthesia, we tested the vasoactivity of acetylcholine (ACh, 10(-8)-10(-5) M), bradykinin (BK, 10(-8)-10(-5) M), and asphyxia (10% O2, 9% CO2, balance N2) after subchronic pretreatment with cocaine. After repeated administration of cocaine (20 mg.kg-1.day-1 sc x 7 days), the BK-induced dilation of pial arterioles was reduced by 51%. Previous work showed that BK produces dilation of pial arterioles by a cyclooxygenase-dependent oxygen radical-mediated mechanism and that in rabbits the BK-induced dilation is dependent on both vascular and nonvascular cyclooxygenase. Selective blockade of vascular cyclooxygenase, in addition to cocaine treatment, did not produce any greater inhibition of the BK-induced dilation. The dilation in response to ACh and asphyxia was unaltered by cocaine. Levels of cerebrospinal fluid prostaglandins suggest cocaine pretreatment may inhibit cerebral vascular prostaglandin production. Together, cerebrospinal fluid prostaglandin and vasoreactivity data indicate cocaine pretreatment selectively inhibits the vascular cyclooxygenase-dependent mechanism mediating the BK-induced dilation. This decreased response to BK in cocaine-treated rabbits may result from decreased oxygen radical production concomitant with decreased vascular prostaglandin production. Alternatively, oxygen radical scavenging may be increased after cocaine treatment. We speculate that cocaine-induced alterations in cerebrovascular function and metabolism may be related to the increased incidence of stroke reported to occur in human cocaine users.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1576-83
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Repeated cocaine administration reduces bradykinin-induced dilation of pial arterioles.
pubmed:affiliation
Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0613, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't