Objective To observe the effect of moxibustion of"Baihui"(GV 20)

etc.on learning-memory ability

hippocampal amyloidβ(Aβ)protein expression and immune activity in mild cognitive impairment(MCI)rats

so as to reveal its mechanism underlying improving cognitive impairment.Methods A total of 48 SD rats were randomly divided into normal

model

moxibustion

and medication groups(n=12in each group).The MCI model was established by intraperitoneal injection of2 mL mixture solution containing D-galactose(120 mg·kg-1·d-1)and Sodium Nitrite(90 mg·kg-1·d-1)

once daily for40 days.Moxibustion(separated by Radix Aconiti Praeparata cake)was applied to "Baihui"(GV 20)

"Fengfu"(GV 16)and"Dazhui"(GV 14)for 20 min

once daily for 2weeks

with one day's rest between two weeks.The rats of the medication group were given with Nimodipine(2mg·kg-1·d-1

t.i.d.)by lavage for 2weeks(except Sundays).The learning-memory ability was detected by Morris maze water swimming tasks.The expression level of hippocampal Aβprotein was detected by immunohistochemistry

and those of hippocampal presenilin-1(PS-1)mRNA and cleaving enzyme(BACE-1)mRNA were detected by real time-PCR

and serum IL-6level was assayed by ELISA.Results Following modeling

the average escape latency of location navigation tests of Morris maze water swimming tests

the expression levels of hippocampal Aβprotein

PS-1mRNA and BACE-1mRNA

and serum IL-6content were significantly increased in the model group(P<0.01)

while the target-platform crossing times and the percentage of target-quadrant swimming duration of spacial probe trials were remarkably decreased in the model group(P<0.01).After moxibustion

the increased escape latency

hippocampal Aβprotein

PS-1mRNA and BACE-1mRNA expression and serum IL-6content

and the decreased target-platform crossing times and the percentage of target-quadrant swimming duration were reversed in both moxibustion and medication groups(P<0.01).The effects of the moxibustion group were obviously superior to those of the medication group in decreasing the escape latency

and in up-regulating the target-platform crossing times

the percentage of target-quadrant swimming duration

and down-regulating hippocampal Aβprotein

PS-1mRNA and BACE-1mRNA expression levels and serum IL-6content(P<0.05).Conclusion Moxibustion is effective in improving MCI rats' learning-memory ability

which may be associated with its functions in down-regulating the levels of hippocampal Aβprotein

PS-1mRNA and BACE-1mRNA expression and serum IL-6content

possibly by blocking Aβoverexpression-induced inflammation cascade.