ABSTRACT
<p><b>OBJECTIVE</b>To screen out active substances on Neuromedin U2 receptor (NMU2R) by using stable NMU2R cell lines and negative cell lines and analyzing siRNA interference.</p><p><b>METHOD</b>NMU2R cells were used to observe the activating effect of nine nine citrus flavonoids on NMU2R cell. Afterwards, false-positive interference of citrus flavonoids that showed higher activating effect was eliminated by using negative cells and analyzing the efficiency of siRNA interference.</p><p><b>RESULT</b>Hesperidin and nobiletin contained in citrus flavonoids were found to effectively activate NMU2R. The efficacy, EC50 and potency values of hesperidin were 4.688, 318.970 micromol x L(-1) and 200.933 micromol x L(-1), while the efficacy, EC50 and potency values of nobiletin were 4.758, 5.832 micromol x L(-1) and 3.124 micromol x L(-).</p><p><b>CONCLUSION</b>Hesperidin and nobiletin contained in citrus flavonoids can activate NMU2R. Nobiletin shows such a low EC50 that it has medicinal value.</p>