Objective To investigate the effects and possible mechanism of Shenmai Injection（参麦注射液） on hypertensive heart failure. Methods A total of 20 Dahl/SS salt-sensitive male rats were randomly divided into three groups: A normal group with 6 rats was given low-salt diet for 20 weeks; a model group（n=7） and a Shenmai Injection group（n=7） were given 20 g high-salt diets（8% sodium chloride） for 20 weeks to establish a rat model of hypertension heart failure. Left ventricular ejection fraction（LVEF） and left ventricular shortening fraction（LVFS） were detected by echocardiography. Serum amino-terminal brain natriuretic peptide（NT-proBNP） levels were measured. Rat urine was collected for liquid chromatography mass spectrometry（LC-MS） combined with technical analysis to screen differential metabolites and analyze related metabolic pathways. Results Compared with the normal group

LVEF and LVFS in the model group decreased

and serum NT-proBNP levels increased（P<0.01）. Compared with the model group

the LVEF and LVFS in the Shenmai Injection group increased

and the serum NT-proBNP level decreased（P<0.01）. The urine metabolic profile of the 3 groups of rats showed a clear trend of separation. After intervention with Shenmai Injection

the 6 differential metabolites of 4-pyridoxine

kynuric acid

L-arginine

creatine

inositol

5-L-glutamyl-bovine sulfonic acid had significant changes

and their metabolic pathways involve arginine and proline metabolism. Conclusion Shenmai Injection can normalize abnormal urine metabolism in hypertensive heart failure rats

and its mechanism may be related to regulating amino acid metabolism

energy metabolism and oxidative stress response.