Effects of praeruptorin C on blood pressure and expression of phospholamban in spontaneously hypertensive rats.
BACKGROUND
The traditional Chinese medicine Praeruptorin c (Pra-c) has many physiological and pharmacological effects, including antagonistic effects on blood pressure and calcium levels, maintenance of cellular calcium homeostasis, and improved cardiac systolic and diastolic function. It is potentially a novel and versatile drug for the treatment and prevention of cardiovascular diseases.


OBJECTIVE
To explore the possible impact of Pra-c on blood pressure in SHR and its mechanism of action.


METHODS
Twenty SHR were randomly divided into a Pra-c group [Pra-c was administered intragastrically, 20 mg kg(-1) d(-1), n=10] or an untreated control group (n=10), containing 10 age-matched SD rats. Each group of rats was followed for 8 weeks. Before and during the treatment, tail artery systolic blood pressure was measured using a tail-cuff every 2 weeks. After 8 weeks, the rats were sacrificed and RNA was extracted from homogenates of cardiac tissue. Tissue from the left ventricle was fixed, sectioned and H&E stained to assess possible changes in myocardial cell structure and morphology. Semi-quantitative RT-PCR was used to assess changes in phospholamban gene expression in treated and untreated rats.


RESULTS
SHR treated with Pra-c for 8 weeks had a lower systolic pressure than untreated SHR (p<0.05), two measures of cardiac damage, the heart mass index and left ventricle mass index (HMI and LVMI, respectively) were improved, and the level of PLB mRNA expression was lower in the untreated SHR group (p<0.05).


CONCLUSIONS
With continuous hypertension, SHR gradually formed or developed cardiac hypertrophy and fibrosis. Pra-c had a clear effect on blood pressure in SHR, and reversed SHR ventricular remodeling by upregulating the gene expression of sarcoplasmic reticulum PLB.
Tongling Clinical College of Anhui Medical University, Tongling, Anhui 244000, China.
Wang
W
Wenjie
Tongling Clinical College of Anhui Medical University, Tongling, Anhui 244000, China.
Lu
L
Houqing
Lianyungang Hospital Affiliated to Bengbu Medical College, Lianyungang, Jiangsu 233003, China.
Sun
S
Liming
Tongling Clinical College of Anhui Medical University, Tongling, Anhui 244000, China.
Zhong
Z
Ping
The First Affiliated Hospital of Medical University of Anhui, Hefei, Anhui 230022, China. Electronic address: sungengy@126.com.
Sun
S
Gengyun
D000818:Animals; D019661:Apiaceae / Q000737:chemistry*; D001794:Blood Pressure / Q000187:drug effects*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D006332:Cardiomegaly; D003374:Coumarins / Q000494:pharmacology / Q000627:therapeutic use*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008297:Male; D009206:Myocardium / Q000473:pathology; D008517:Phytotherapy; D051381:Rats; D011918:Rats, Inbred SHR; D020257:Ventricular Remodeling / Q000187:drug effects; D000099211:Phospholamban
D002135:Calcium-Binding Proteins; D003374:Coumarins; D004365:Drugs, Chinese Herbal; D000099211:Phospholamban; C058808:praeruptorin C
Hypertension; Phospholamban; Praeruptorin C; Remodeling; Spontaneously hypertensive rats