Objective: To observe the protective effects of Yishen granule on renal lesion in diabetic nephropathy (DN) rats. Method :DN rats with unilateral nephrectomy induced by STZ with single intraperitoneal injection at the dose of 55 mg·kg-1. Then the rats were randomly divide into the unilateral nephrectomy group

DN model group

Yishen granule groups in low and high dose (8.1

16.2 g·kg-1)

the positive control medicine group with lotensin(1.5×10-3 g·kg-1). The different drugs were given by intragastrical administration once a day and lasted 16 weeks. The rats in the unilateral nephrectomy group and DN model group were given isovolumetric distilled water. It was been observed that the effects of the different drugs on the serum levels of laminin(LN) and type Ⅳ collagen

as well as renal ultramicrostructure. Result: The serum levels of LN and type Ⅳ collagen were significantly decreased in Yishen granule high-dose group. It was been observed that the foot processes of podocytes

basement membrane thickening and endocapillary proliferation in glomerular filtration membrane were significantly alleviated in two Yishen granule groups. Conclusion: Yishen granule could improve renal tissue by decreasing the serum levels of LN and type Ⅳ collagen and inhibiting pathological changes of glomerular ultramicrostructure in DN.