RESUMO
<p><b>OBJECTIVE</b>To screen the active ingredients of Chailing decoction (CLD) by using rat nephritis model induced by mono-colonal antibody 1-22-3 (mAb) injection.</p><p><b>METHODS</b>The active ingredients of CLD was screened by 5 successive times of experiment. In each time, 28 rats were randomly divided into 4 groups, 7 in each. Group 1 was treated with PBS as control, Groups 2-4 were treated separately with CLD and its various ingredients, the medication was started 5 days before and lasted to 8 days after modeling by peritoneal injection, 13 days totally. All the rats were killed 8 days after modeling to observe the effect of various drugs on proteinuria, morphological change of kidney and biochemical parameters.</p><p><b>RESULTS</b>CLD, Xiaochaihu decoction, various combination of thorowax root and its extract (saikosaponin-d) could reduce urinary protein, inhibit the proliferation of mesangial cell and expansion of extracellular matrix.</p><p><b>CONCLUSION</b>CLD and its active ingredients had inhibition on mAb induced rat model of nephritis, the active is saikosaponin-d.</p>