OBJECTIVETo observe the effects of Zhizhu Tongbian Decoction (ZTD) on the enteric nervous system, mRNA expressions of glial cell line derived neurotrophic factor (GDNF) and nitric oxide synthase (NOS) in the slow transit constipation (STC) rats.

METHODSThirty STC rat model was established by gastric irrigation of rhubarb. After the model building, they were randomly divided into three groups, i. e., the model group, the high dose ZTD group, and the low dose ZTD group, 10 in each. Another 10 rats were selected as the blank control group. Rats in the high dose ZTD group and the low dose ZTD group were administered with ZTD (at the daily dose of crude drug 4.8 g/kg and 2.4 g/kg respectively) by gastrogavage. Normal saline was given to rats in the blank control group and the model group. The ink propelling rate was determined using ink propelling test. Meantime, mRNA expressions of GDNF and NOS in the rat colon were measured using reverse transcriptional polymerase chain reaction (RT-PCR).

RESULTSCompared with the blank control group, the ink propelling rate and GDNF mRNA expression decreased, and NOS mRNA increased in the model group, showing statistical difference (P<0.01, P<0.05). Compared with the model group, the ink propelling rate increased in the high and low dose ZTD groups (P<0.01, P<0.05). The mRNA expressions of GDNF increased and the mRNA expressions of NOS decreased in the high dose ZTD group with statistical difference (P<0.01, P<0.05). But there was no difference in any index between the high and low dose ZTD groups.

CONCLUSIONHigh dose ZTD could obviously improve the intestinal transmission function possibly through up-regulating the mRNA expressions of GDNF and down-regulating the mRNA expressions of NOS in STC rats.