Objective To observe the effects of pre-electroacupuncture at “Taichong”(LR3)

“Neiguan”(PC6) and “Waiguan”(TE5) on blood pressure and cardiac function of high-salt-induced hypertension rats

so as to explore the possible mechanism of pre-electroacupuncture in improving hypertension. Methods Twenty-four SD rats were randomly divided into control group

high-salt group and pre-electroacupuncture group

with 8 rats in each group. The hypertension model was established by feeding high-salt diet for 7 weeks. In the pre-electroacupuncture group

rats received electroacupuncture intervention at bilate-ral LR3

PC6 and TE5(2 Hz/15 Hz

2 mA) for 30 min

once a day

from the first day of modeling

for a total of 7 weeks. The blood pressure of rats was monitored by caudal artery noninvasive blood pressure measurement technique before and at the 1

(st)

3(st)

3

(rd)

5(rd)

5

(th)

and 7(th) and 7

(th)

week of modeling. At the 8(th) week of modeling. At the 8

(th)

week of the experiment

left ventricular catheterization was performed and biological signal acquisition system was used to detect left ventricular hemodynamics indexes and analyze left ventricular function

the car-diac mass ratio was measured to evaluate the degree of myocardial hypertrophy. The mRNA expressions of atrial natriuretic peptide(ANP)

myosin heavy chain 7(MYH7)

α-smooth muscle actin(α-SMA)

interleukin(IL)-1β

and IL-6 of myocardial tissues were detected by quantitative real-time PCR. Sirius red staining was used to observe the degree of myocardial fibrosis. Results Compared with the control group

systolic blood pressure

diastolic blood pressure

mean arterial pressure

left ventricular end-diastolic pressure(LVEDP)

cardiac mass ratio

and the mRNA expressions of ANP

MYH7

α-SMA

IL-1β

and IL-6

and sirius red staining area of myocardium were all significantly increased(P

<

0.01

P

<

0.05)

maximal rate of rise and descent of left ventricular pressure(LVP±dP/dt _(max)) were decreased(P

<

0.05

P

<

0.01) in the high-salt group. Compared with the high-salt group

rats in the pre-electroacupuncture group had lower systolic blood pressure

diastolic blood pressure

mean arterial pressure

LVEDP

cardiac mass ratio

higher LVP±dP/dt_(max)

down-regulated mRNA expressions of ANP

MYH7

α-SMA

IL-1β

IL-6

and smaller area of sirius red staining(P

<

0.05

P

<

0.01). Conclusion Pre-electroacupuncture tends to lower blood pressure

improve cardiac function and reduce myocardial fibrosis in high-salt-induced hypertension rats

which may be associated with inhibiting inflammatory response.