Objective: To study the effect of Meicha protein on blood pressure and blood vessels of spontaneously hypertensive rats (SHR) rats after continuous administration

and explore its mechanism. Method: Totally 40 male SHR were randomly divided into model (equal volume of distilled water)

positive control group (compound Kendir leaves tablets

50 mg·kg-1)

and low and high-dose Meicha protein groups (70

140 mg·kg-1). Each group was intragastrically administrated with drugs (10 mL·kg-1) once in the morning and afternoon for 7 weeks. The blood pressure at rat tail artery was measured before administration

and after administration once a week. The blood and thoracic aorta were collected after the last administration to detect the content of nitric oxide (NO) and endothelin-1 (ET-1) in the serum

and the mRNA expressions of endothelial nitric oxide synthase(eNOS)

angiotensin converting enzyme(ACE)

angiotensin Ⅱ(Ang Ⅱ)

c-Myc

p27 and B cell lymphoma/leukemia-2(Bcl-2) gene in the blood vessels. Result: Compared with model group

low and high-dose Meicha protein groups can significantly decrease the blood pressure of SHR since the second week

increase the content of NO

reduce the content of ET-1

inhibite the expressions of gene c-Myc

Bcl-2 and ACE

and enhance the mRNA expression of eNOS (P<0.05

P<0.01)

but with no effect on p27 mRNA. Conclusion: Meicha protein has significant antihypertensive and vascular-protective effects on SHR. The mechanism may be correlated with the changes in the level of NO and ET-1 in the serum

and the expressions of gene c-Myc

Bcl-2

ACE

Ang Ⅱ and eNOS in the blood vessel.