Linked Life Data

15448979

Source:http://linkedlifedata.com/resource/pubmed/id/15448979

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2004-11-19
pubmed:abstractText
The effects of angiotensin II and angiotensin III were compared at prejunctional and postjunctional AT(1) receptors of the rabbit thoracic aorta. Furthermore, the influence of PD123319, losartan and eprosartan on these effects was also compared. To study prejunctional effects, the tissues were preincubated with ((3)H)-noradrenaline, superfused and electrically stimulated (1 Hz, 2 ms, 50 mA, 5 min). To study postjunctional effects, non-cumulative concentration-response curves were determined. Both angiotensin II and angiotensin III were more potent prejunctionally than postjunctionally. In the case of angiotensin II, the EC(50) was 12 times lower at the prejunctional than at the postjunctional level, while that of angiotensin III was 30 times lower prejunctionally. Furthermore, whereas angiotensin II was about 33 times more potent than angiotensin III postjunctionally, it was only 12 times more potent than angiotensin III prejunctionally. Eprosartan did not differentiate between prejunctional and postjunctional effects of both angiotensins. In contrast, PD123319 and losartan did differentiate; however, whereas PD123319 concentration-dependently antagonised the facilitation of tritium release caused by angiotensin II and angiotensin III and had no influence on the contraction of the aortic rings elicited by the peptides, losartan did the opposite: it concentration-dependently antagonised the contractions caused by the peptides on the aortic rings and exerted no influence on the facilitatory effect of angiotensin II and angiotensin III. These results show that prejunctional and postjunctional receptors for angiotensin II and angiotensin III are different and underline the hypothesis that postjunctional AT(1) receptors belong to the AT(1A) subtype, while prejunctional AT(1) receptors belong to the AT(1B) subtype.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
370
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
262-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
A pharmacological differentiation between postjunctional (AT1A) and prejunctional (AT1B) angiotensin II receptors in the rabbit aorta.
pubmed:affiliation
Faculdade de Medicina, Instituto de Farmacologia e Terapêutica, Alameda Hernani Monteiro, 4200-319 Porto, Portugal. sguimara@med.up.pt
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't