[Effects of electroacupuncture on CYP7A1 expression in liver of rabbits with atherosclerosis]

To observe the effects of electroacupuncture (EA) at "Neiguan" (PC 6), "Guanyuan" (CV 4) and "Zusanli" (ST 36) on CYP7A1 expression in liver of rabbits with atherosclerosis (AS), and to explore the mechanism of acupuncture for prevention and treatment of atherosclerosis.

A total of 26 male rabbits were adaptively fed for 1 week in different cages. Seven rabbits were randomly divided into a blank group, and the remaining 19 rabbits were divided into a model group. The blank group was fed with normal diet, while the model group was fed with high-fat diet. After high-fat diet for 4 weeks, the rabbits in the model group were treated with balloon injury surgery of the common carotid artery; after surgery, the rabbits were fed with high-fat diet for 4 weeks. One rabbit was randomly selected from the blank group and model group to obtain the pathological section of carotid artery; the HE staining was used to observe the pathomorphology of atheromatous plaque to determine the success of modeling or not. After successful establishment of modeling, 18 rabbits were randomly divided into a AS model group, an EA group and a medication group, 6 rabbits in each one. The rabbits in the AS model group received no treatment; the rabbits in the medication group were treated with intragastric administration of atorvastatin calcium tablets; the rabbits in the EA group were treated with EA at "Neiguan" (PC 6), "Guanyuan" (CV 4) and "Zusanli" (ST 36), once a day, 20 min per treatment; six-day EA treatment constituted one course, and totally 4 courses were given with an interval of 1 day between courses. After treatment, vein blood was collected from rabbit ear, and cholesterol (CHO), triglyceride (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) were measured in each group; the CYP7A1 protein expression in rabbit liver was measured by Western blot method, and CYP7A1 mRNA expression in rabbit liver was measured by RT-PCR.

Compared with the blank group, the contents of CHO, TG and LDL in the AS model group were significantly increased, but HDL was significantly decreased, and the expression of CYP7A1 protein and CYP7A1 mRNA in the liver were significantly decreased (all P<0.01). After treatment, compared with the model group, the contents of CHO, TG and LDL in the EA group and medication group were significantly reduced, but HDL was significantly increased, and the expression of CYP7A1 protein and CYP7A1 mRNA in the liver were significantly increased (all P<0.01). The significant difference of each outcome between the EA group and medication group was not observed (all P>0.05).

EA could significantly improve blood lipid and promote the expression of CYP7A1 mRNA in rabbits with atherosclerotic, which may be one of the mechanisms of EA for atherosclerosis.