To observe the effect of electroacupuncture (EA) stimulation of "Fenglong" (ST 40), "Sanyinjiao" (SP 6) plus manual acupuncture (MA) stimulation of "Shuigou" (GV 26) and "Baihui" (GV 20) on Caspase-3 protein expression in the cerebral cortex of rats with hyperlipemia and cerebral ischemia(HL-CI),so as to reveal its mechanisms underlying improvement of HL-CI.
Forty-five rats were randomly divided into normal control,sham operation,model,EA group I(EA+MA was given for 14 days, i.e., 7 days before CI, and 7 days more after HL-CI)and EA group Ⅱ (EA+MA was given for only 7 days after HL-CI),with 9 rats being in each group. The HL-CI model was established by feeding the animals with high fat forage for 6 weeks and then making an occlusion of the unilateral middle cerebral artery by regional application of quantitative paper adsorbing 50% FeCl3 solution (10 μL). Rats of the sham operation group were treated with the same procedures only without application of FeCl3 solution. For rats of the EA group I,EA (1-3 mA, 2 Hz/100 Hz) was applied to bilateral acupoints SP 6 and ST 40 (for 20 min),and MA stimulation applied to GV 26 and GV 20. EA was conducted once daily for 7 days after 6 weeks' high fat fo-rage feeding, and EA+MA intervention was conducted once daily for 7 days after CI modeling. For rats in the EA group Ⅱ, EA+MA was applied to the same 4 acupoints once a day for 7 days only after CI modeling. The neurological impairment was assessed by Zea Longa's scoring. The blood sample was taken from the abdominal aorta for measuring the contents of serum cholesterol (CHO),triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Pathological changes of the cerebral cortex were observed after H.E. staining, and the expression of cerebro-cortex Caspase-3 was analyzed by immunohistochemistry.
Following modeling,the neurological score,CHO, TG and LDL-C contents, and the number of Caspase-3 positive cells as well as Caspase-3 immunoactivity level were significantly increased in the model group(P<0.05), while serum HDL-C level was obviously decreased(P<0.05). After the treatment,the increased neurological score, CHO, TG and LDL-C contents, and the number of Caspase-3 positive cells and Caspase-3 immunoactivity level were considerably decreased in the EA group I and Ⅱ(P<0.05)while the decreased HDL-C level was notably increased relevant to the model group(P<0.05). The effects of the EA group I were notably superior to those of EA group Ⅱ in down-regulating the neurological score,CHO, TG and LDL-C levels and the expression of Caspase-3 protein(P<0.05). No significant differences were found between the normal control and sham operation groups in the neurological scores 20 min and 7 days after modeling and Caspase-3 expression levels (P>0.05). H.E. staining showed a reduction of the apoptotic cells and inflammatory cells in both EA group I and Ⅱ.
Both EA and EA+MA interventions can improve neurological function in HL-CI rats,which may be related to their effects in adjusting the levels of serum lipids and down-regulating the expression of cell apoptosis-related Caspase-3 protein in the ischemic cortex. Moreover, the cerebral ischemia injury may be lightened by EA-lowering hyperlipemia first.