Abstract
Experimental data indicate the renin-angiotensin system contributes to the development of left ventricular hypertrophy (LVH) in response to pressure-overload. A previous study showed that 21 (young;Y) and 42 (adult;A) day old rats exhibited LVH following 10 days of pressure-overload. Young rats exhibited hyperplasia while adult rats exhibited hypertrophy. However, only adult rats demonstrated cardiac compromise. The objective of this study was to examine angiotensin II (An) receptor binding kinetics in young and adult rat left ventricle membrane preparations following 10 days of pressure-overload. Pressure-overload was induced by suprarenal abdominal aortic constriction (AC); aged-matched sham-operated (SO) rats were controls. Carotid artery mean arterial pressure (MAP) and heart rate (HR) were determined. The left ventricle was removed for determination of LVH and An receptor binding. Data are reported as mean±SD and p<0.05 (+) as statistically significant. Young and adult rats exhibited an increase in MAP and LVH; however, only adult rats had a reduced HR. Ail receptor BW(grns) LV(gmsJi %LV:BW MAP HR Y-AC 72±11.y ÖT306±Ö.Ö5' 473310.65' 1241T6 ' 393±27 Y-SO 79±8.5 0.247±0.02 3.1210.08 95±4 376±29 A-AC 271±20+ 0.813±0.07' 3.0U0.34' 143±8' 381±28' A-SO 298117 0.66810.04 2.2510.09 10718 405±32 binding in Y-AC and Y-SO rats revealed a high affinity site with a similar Kd (2.6 vs. 3.1 nM) and Bmax (42.1 vs. 53.2 fmol/mg protein). Similar findings were observed between A-AC and A-SO rats. The lack of changes in An binding kinetics between AC and SO rats suggest that All receptors are not responsible for the early development of LVH in this model.
| Original language | English |
|---|---|
| Pages (from-to) | A308 |
| Journal | FASEB Journal |
| Volume | 10 |
| Issue number | 3 |
| State | Published - 1996 |
ASJC Scopus subject areas
- Biotechnology
- Biochemistry
- Molecular Biology
- Genetics