Item Type: | Article |
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Title: | Expression of an angiotensin-(1-7)-producing fusion protein produces cardioprotective effects in rats |
Creators Name: | Santos, R.A.S., Ferreira, A.J., Nadu, A.P., Braga, A.N.G., de Almeida, A.P., Campagnole-Santos, M.J., Baltatu, O., Iliescu, R., Reudelhuber, T.L. and Bader, M. |
Abstract: | Angiotensin-(1-7) [ANG-(1-7)] is a recently described heptapeptide product of the renin-angiotensin system. Because biosynthesis of ANG-(1-7) increases in animals treated with cardioprotective drugs and inactivation of the gene for angiotensin converting enzyme 2 [an enzyme involved in the biosynthesis of ANG-(1-7)] leads to the development of cardiac dysfunction, it has been suggested that ANG-(1-7) has cardioprotective properties. To directly test this possibility, we have generated transgenic rats that chronically overproduce ANG-(1-7) by using a novel fusion protein methodology. TGR(A1-7)3292 rats show testicular-specific expression of a cytomegalovirus promoter-driven transgene, resulting in a doubling of circulating ANG-(1-7) compared with nontransgenic control rats. Radiotelemetry hemodynamic measurements showed that transgenic rats presented a small but significant increase in daily and nocturnal heart rate and a slight but significant increase in daily and nocturnal cardiac contractility estimated by dP/d t measurements. Strikingly, TGR(A1-7)3292 rats were significantly more resistant than control animals to induction of cardiac hypertrophy by isoproterenol. In addition, transgenic rats showed a reduced duration of reperfusion arrhythmias and an improved postischemic function in isolated Langendorff heart preparations. These results support a cardioprotective role for circulating ANG-(1-7) and provide a novel tool for evaluating the functional role of ANG-(1-7). |
Keywords: | Engineered Protein, Heart Hypertrophy, Renin-Angiotensin System, Animals, Rats |
Source: | Physiological Genomics |
ISSN: | 1094-8341 |
Publisher: | American Physiological Society |
Volume: | 17 |
Number: | 3 |
Page Range: | 292-299 |
Date: | 1 January 2004 |
Official Publication: | https://doi.org/10.1152/physiolgenomics.00227.2003 |
PubMed: | View item in PubMed |
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