Effects of Losartan and Amlodipine on Left Ventricular Remodeling and Function in Young Stroke-Prone Spontaneously Hypertensive Rats.
BACKGROUND
The purpose of this study was to evaluate the effects of prehypertensive losartan and amlodipine administration on left ventricular (LV) remodeling and function in spontaneously hypertensive rats-stroke prone (SHRSP).


METHODS
Spontaneously hypertensive rats-stroke prone were prehypertensively administered losartan, amlodipine, or vehicle. Wistar-Kyoto rats were used as a control. Blood pressure of the rats was determined by tail-cuff method, and LV structure and function were measured by echocardiography and LV cannulation. Collagen volume fraction was analyzed by picrosirius red staining. Protein expressions of brain natriuretic peptide (BNP) and angiotensin II type 1 (AT1R) and type 2 (AT2R) receptors were determined by use of the Western blotting method.


RESULTS
Although both drugs downregulated BNP protein expression, the LV remodeling and function were more improved with losartan than with amlodipine treatment. Losartan upregulated AT1R and downregulated AT2R protein expression.


CONCLUSIONS
Both drugs inhibited LV remodeling and improved LV function in prehypertensively treated SHRSP. Losartan provided better continued heart protection, potentially due to its persistent inhibition of AT1R and activation of AT2R in the myocardium.


BACKGROUND
Amlodipine; Blood pressure; Heart; Losartan; Prehypertension.
Department of Cardiology, First Affiliated Hospital of Xiamen University; ; Department of Cardiology, First Clinical Medical College of Fujian Medical University, Fujian;
De-Hua
DH
He
Department of Cardiology, People's Hospital of Ningdu County, Jiangxi;
Liang-Min
LM
Zhang
Department of Cardiology, Affiliated Hospital of Putian College;
Li-Ming
LM
Lin
Department of Cardiology, First Clinical Medical College of Fujian Medical University, Fujian;
Ruo-Bing
RB
Ning
Fujian Institute of Hypertension, Fujian, China.
Hua-Jun
HJ
Wang
Fujian Institute of Hypertension, Fujian, China.
Chang-Sheng
CS
Xu
Department of Cardiology, First Clinical Medical College of Fujian Medical University, Fujian;
Jin-Xiu
JX
Lin