Objective To investigate the effect of oculo-acupuncture therapy(OAT) on the alteration of colonic serotonin reuptake transporter(SERT) expression in rats with irritable bowel syndrome(IBS) so as to explore its underlying mechanism in relieving IBS.Methods Thirty male Wistar rats were randomized into control

IBS model and OAT groups(n=10/group).IBS model was established by repeated stress stimulation [water-intake inhibition(24h)

warm box keeping(40℃

5min)

electric shock stimulation(30V

120s)

forced cool water swimming(14℃

5min)

24h fasting

and tail clamping(180s)] for 18 days.Oculo-acupuncture stimulation was given to "Xiajiao"(Lower Energizer)

"Dachang"(Large Intestine)

"Gan"(Liver) and "Pi"(Spleen) areas for 20min by using filiform acupuncture needles(manipulated 1min once every 10 min).The treatment was conducted once every 12h for 7 days.Colonic SERT mRNA and protein expression levels were examined by RT-PCR and Western Blot.Results In comparison with the control group

the expression levels of both colonic SERT mRNA and protein in the model group were down-regulated remarkably(P<0.05).Compared with the model group

the expression levels of SERT gene and protein in the OAT group were increased remarkably(P<0.05).Conclusion OAT can increase colonic SERT protein and gene expression in IBS rats

which may play a role in relieving IBS in OAT clinic.