Objective To observe the effect of electroacupuncture(EA) at "Fenglong"(ST 40) on blood lipid levels and hepatic ATP binding cassette transporter A 1(ABCA 1) mRNA and protein expression in hyperlipidemia rats

so as to study its mechanism underlying improvement of HLP.Methods Forty SD rats were randomized into normal control

model

diet control

EA

and EA+diet control groups

with 8 rats in each group.Hyperlipidemia model was established by feeding the animals with high fat forage for 28 days.After modeling

rats of the two diet control groups were fed with basal forage.EA(2 mA

2 Hz/100 Hz) was applied to bilateral ST 40 for 30 min

once daily for 28 days.Plasma total cholesterol(TC)

triglyceride(TG)

low-density lipoprotein cholesterol(LDL-C)

and high-density lipoprotein cholesterol(HDL-C) contents were detected by automatic biochemistry analyzer

and the expression levels of ABCA 1 mRNA and protein in the liver tissue were assayed by in situ hybri-dization(ISH)

RT-PCR and Western blot

respectively.Results Compared with the normal control group

the contents of plasma TC and LDL-C were apparently increased(P<0.01) and the expression levels of hepatic ABCA 1 mRNA(detected by both ISH and RT-PCR) and ABCA 1 protein were significantly decreased in the model group(P<0.01).In comparison with the model group

plasma TC and LDL-C contents were significantly decreased and the expression levels of hepatic ABCA 1 mRNA and protein were significantly up-regulated in the EA group and EA+diet control group(P<0.01).The effects of EA+diet control were significantly superior to those of diet control in down-regulating plasma TC and LDL-C levels and up-regulating hepatic ABCA 1 mRNA and protein expression levels(P<0.01).Conclusion EA stimulation of "Fenglong"(ST 40) can decrease the load of blood cholesterol and suppress the down-regulation of hepatic ABCA 1 mRNA and protein expression in hyperlipidemia rats

which may contribute to its effect in improving hyperlipidemia.