Please use this identifier to cite or link to this item:
|Title:||Effects of des-aspartate-angiotensin I on the expression of angiotensin AT1and AT2receptors in ventricles of hypertrophic rat hearts|
|Citation:||Chen, W.S., Sim, M.K. (2004). Effects of des-aspartate-angiotensin I on the expression of angiotensin AT1and AT2receptors in ventricles of hypertrophic rat hearts. Regulatory Peptides 117 (3) : 207-212. ScholarBank@NUS Repository. https://doi.org/10.1016/j.regpep.2003.10.017|
|Abstract:||The effects of des-aspartate-angiotensin I (DAA-I) on the expression of angiotensin AT1 and AT2 receptor in hearts of aortic coarcted rats were studied. The protocols used included competitive reverse transcription polymerase chain reaction (RT-PCR), Western blotting, and receptor-ligand binding assays. mRNA of the AT1 and AT2 receptors increased significantly after 4 days of aortic coarctation (7- and 4-folds of sham-operated, respectively). However, the protein of the AT 1 receptor was not altered, and only increase in protein of the AT2 receptor was detected. There was an increase in [ 125I]Sar1-Ile8-angiotensin II binding sites in the ventricular membranes of hypertrophic hearts, which was attributed to an upregulation of the AT2 receptor. Treatment with i.p. DAA-I resulted in a significant reduction of cardiac hypertrophy, the maximum effect was achieved with a dose of 200 nmol/kg/day. The anti-cardiac hypertrophy effect appeared to be U-shape, and at a higher dose of 800 mol/kg/day, there was a loss of effect. DAA-I had no effect on the receptor protein in ventricles of hypertrophic hearts. However, DAA-I dose-dependently decreased the binding of [125I]Sar1-Ile8-angiotensin II to ventricular membranes. The decrease was due to a likely desensitization by internalization of the AT1 receptor, and this probably contributed to the loss of hypertrophic effects at 800 nmol/kg/day. Treatment of DAA-I also resulted in a remarkable increase in AT2 receptor mRNA (24-fold increase over the sham-operated), which was not coupled to translation. The present findings provide new information regarding the relationship between cardiac hypertrophy and the angiotensin receptors, and the anti-cardiac hypertrophic actions of DAA-I via the AT1 receptors. © 2003 Elsevier B.V. All rights reserved.|
|Source Title:||Regulatory Peptides|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Aug 10, 2018
WEB OF SCIENCETM
checked on Jul 9, 2018
checked on Jul 28, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.