Objective To explore the mechanism of acupuncture in improving cognitive ability by regulating hippocampal phosphatidylinositol-3 kinase(PI3 K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway in vascular dementia(VD) rats.Methods A total of 80 male SD rats were randomized into sham operation

model

non-acupoint and acupoint groups(n=18 per group). The VD model was established by ligation of the bilateral common carotid arteries. For rats of the acupoint group

“Baihui”(GV20) and bilateral “Zusanli ”(ST36) were needled and stimulated by twirling the needles with reinforcing method

and for rats of the non-acupoint group

the bilateral subcostal spots(about 10 mm superior to the iliac cresta) were needled and stimulated by twirling the needles with uniform reinforcing and reducing method. The treatment was conducted once daily

6 times a week for two weeks

beginning 3 days after successful modeling. Rats of the sham operation group and model group received grasps as those in the acupoint groups. Morris water maze test was used to detect the abilities of learning and spatial memory. The contents of reactive oxygen species(ROS)

malondialdehyde(MDA)

superoxide dismutase(SOD) and the activities of acetylcholinesterase(AChE) and acetylcholine transferase(ChAT) in the hippocampus tissue were detected by using ELISA

changes of hippocampal mitochondrial membrane potential(MMP) detected using JC-1 fluorescence probe

and the expression levels of hippocampal phosphorylated(p)-PI3 K

p-Akt and mTOR proteins measured using Western blot. Results Compared with the sham operation group

the escape latency

contents of ROS and MDA

and AChE activity were significantly increased(P<0.05)

and the spatial memory ability

SOD activity

ChAT activity

MMP

p-PI3 K

p-Akt and mTOR expression levels were significantly decreased in the model group(P<0.05). Compared with the model group

carotid artery ligature-induced increase of the escape latency

contents of ROS and MDA

and AChE activity

and decrease of the spatial memory ability

SOD activity

ChAT activity

MMP

p-PI3 K

p-Akt and mTOR expression levels were significantly reversed in the acupuncture group(P< 0.05)

but not in the non-acupoint group(P>0.05). The therapeutic effects of acupoint needling were obviously superior to those of non-acupoint needling in decreasing the escape latency

contents of ROS and MDA

and AChE activity(P<0.05)

and in increasing the spatial memory ability

SOD activity

ChAT activity

MMP

p-PI3 K

p-Akt and mTOR expre-ssion levels(P<0.05). Conclusion Acupuncture can improve cognitive function of VD rats

which may be related with its functions in easing oxidative stress and MMP reduction by activating PI3 K/Akt/mTOR signaling pathway in the hippocampus.