Objective To observe the effect of moxibustion on learning-memory ability and expression of hippocampal inflammatory factors and microtubule-associated protein doublecortin(DCX

a marker of neuronal regeneration) in vascular dementia(VD) rats

so as to explore its mechanisms underlying improvement of VD. Methods SD rats were randomly divided into normal control

sham operation

VD model

moxibustion and medication groups(n=15 rats in each group). The VD model was established by repeated occlusion of the bilateral common carotid arteries and reperfusion. Moxibustion was applied to "Guanyuan"(CV4)

"Mingmen"(GV4) and "Dazhui"(GV14) for 15 min

once a day

6 days a week for 4 weeks. Rats of the medication group were treated by gavage of Nimodipine(2 mg·kg

(-1)

·d(-1)·d

(-1)

) 3 times daily for 4 weeks. Morris water maze test was used to detect the average escape latency of location navigation tasks for assessing the rats' learning-memory ability. H.E. staining was used to detect histopathological changes of the hippocampus tissue. The number of DCX-positive neurons(DCX/NeuN co-expression) in the dentate gyrus(DG) region of hippocampus was counted under microscope after immunofluorescence double staining

the immunoactivity of hippocampal DCX detected by using immunohistochemistry stain and the expression of DCX

TNF-α

IL-1β

MPO

NF-κB p65 and IL-6 proteins in the hippocampus tissue detected using Western blot.Results Following modeling

the average escape latency was significantly longer in the model group than in the normal control and sham operation groups(P

<

0.01)

and notably shorter in both the moxibustion and medication groups than in the model group after the treatment(P

<

0.01

P

<

0.05). The number of DCX-positive neurons

and the expression levels of DCX

TNF-α

IL-1β

MPO

NF-κB p65 and IL-6 proteins in the hippocampus were significantly increased in the model group in comparison with the normal control and sham operation groups(P

<

0.01

P

<

0.05). After the interventions and in comparison with the model group

the number of DCX-positive neurons and the expression level of DCX were further up-regulated in both moxibustion and medication groups(P

<

0.01)

while the expression levels of hippocampal TNF-α

IL-1β

MPO

NF-κB p65 and IL-6 proteins were considerably down-regulated in the moxibustion and medication groups(P

<

0.01). The effect of moxibustion was weaker than that of medication in down-regulating the expression of TNF-α

MPO

NF-κB p65

IL-6 and IL-1β

and in up-regulating DCX-positive neuron number and DCX expression(P

<

0.05

P

<

0.01). H.E. staining showed loose arrangement of neurons(with vague neuronal membrane in some cells)

uneven organelle chromatin

disappearance of partial nucleolus

necrocytosis

and infiltration of small number of lymphocytes after modeling

which was relatively milder in both moxibustion and medication groups. Conclusion Moxibustion can improve learning-memory ability in VD rats

which may be related to its effect in down-regulating the expression of inflammatory factors and up-regulating the expression of DCX to promote neuronal repair and regeneration.