Objective: To study if the spinal glial cells involve in the protective effect of acupuncture on gastric mucosa in high humid heat stress rats.Methods: Thirty-six male SD rats were randomized into 6 groups: control

stress model

electroacupuncture(EA)

Fluorocitrate(FCA

intrathecal injection of FCA

1 μL

60 min before humid heat stress)

EA+normal saline(NS

intrathecal injection of NS) and EA+FCA groups.Stress model was established by putting the rats in a container with higher temperature and higher humidity [(40.0±0.5) ℃

relative humidity(60±5) %] for 60 min.EA(50 Hz

intermittent waves

2-5 V) was applied to bilateral "Zusanli"(ST 36) for 60 min.Using immunofluorescent methods

we observed glial fibrillary acidic protein(GFAP) and microglia OX42 immunoreactivity(OD value) in the tissue of the lumbar enlargement segment of the spinal cord.We evaluated and recorded the damage index(DI) of gastric mucosa of rats according to Guth's method.Results: There were clear dot-line-like hemorrhage foci with formation of ulcer in the gastric mucosa 60 minutes after high humid heat stimulation. Compared with model group

DI of gastric mucosa in EA and EA+NS groups decreased significantly(P<0.05

suggesting a protective effect of EA on the gastric mucosa under stress)

OD values of EA and EA+NS groups increased considerably(P<0.05).Comparison between EA and EA+FCA groups showed that DI of EA+FCA group was higher than that of EA group

while the OD values of GFAP and OX42 in EA+FCA group was markedly lower than those in EA group(P<0.05)

suggesting an inhibitory effect of FCA on the effects of EA in improving stress-induced damage of gastric mucosa and upregulation of GFAP and OX42 expression.Conclusion: EA at "Zusanli"(ST 36) can prevent the gastric mucosa from injury caused by high humid heat stimulation.The lumbar spinal glial cells may play a role in EA's protective function.