[Effects of oculo-acupuncture therapy on colonic serotonin reuptake transporter expression in rats with irritable bowel syndrome].

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 (24 h), warm box keeping (40 degrees C,5 min), electric shock stimulation (30 V, 120 s), forced cool water swimming (14 t, 5 min), 24 h fasting, and tail clamping (180 s)] for 18 days. Oculo-acupuncture stimulation was given to "Xiajiao" (Lower Energizer), "Dachang" (Large Intestine), "Gan" (Liver) and "Pi" (Spleen) areas for 20 min by using filiform acupuncture needles (manipulated 1 min once every 10 min). The treatment was conducted once every 12 h 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.