OBJECTIVETo study organic anion transporting polypeptide (OATP) superfamily member 4a1 (oatp4a1) mRNA expression in the Pi deficiency model rats, thus exploring its mechanism for transporting and transforming the dampness.

METHODSSix SD rats of SPF grade were used to prepare over-fatigue impairing Pi model. Another 12 SD rats were randomly divided into the blank control group and the high fat diets group, 6 in each. The special binding tube was used for the over-fatigue impairing Pi model group on the odd day, 3 h each time. Then the rats were forced to swim in the cold water (10 degrees C +/- 1 degrees C) for 7 min on the even day, for 2 successive weeks. Rats in the model group and the blank control group were granulated feed for 12 weeks, while rats in the high fat group were fed with high fat diet for 12 weeks. All rats were free to take food and drink water. The mRNA and protein expressions of oatp4al were detected in the Fei, Pi, Gan, Shen, Wei, Xiaochang, and Dachang using Real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) and Western blot.

RESULTSRats in the model group were idled together with lousy defecate and coarse skin. They ate and drank less, and lost body weight (P<0.05). They were consistent with clinical manifestations of Pi deficiency syndrome, indicating that the over-fatigue impairing Pi animal model was successfully established. Rats in the high fat group started to have poor appetite and languish spirit, move lazily and addict to sleep, have coarse, dark, and colorless hair 9 weeks later, indicating phlegm dampness syndrome. Compared with the blank control group, the average body weight increased in the high fat group at the 9th week (P<0.05). The oatp4a1 mRNA expressed in the Fei, Pi, Gan, Shen, Wei, Xiaochang, and Dachang. There was no statistical difference in the oatp4al mRNA expression among all tissues (P>0.05). The oatp4al mRNA expressions were higher in the Fei and Shen of the high fat group than in the Gan (P<0.05).

CONCLUSIONSoatp4al might be one of the basic substances in the transportation and transformation of phlegm dampness. Of them, Fei, Shen, and Dachang might play important roles in the transportation and transformation of phlegm dampness.