Abstract:

Abstract:Objective By observing the expressions of vascular endothelial growth factor (VEGF),metallothionein(MT),and matrix metalloprteinase-9 （MMP-9） in the  kidneys of normal and diabetic rats,the influences of exogenous Zn    in kindey and the expessions of VEGF,MT and MMP-9 in kidney tissues of diabetic rats were explored. Methods   Forty-eight Wistar rats were randomly divided into four groups(n=12) :   normal control  (NC)　group,negative control (STZ)group,external Zn intervention diabetic (STZ+Zn) group　and external Zn intervention normal (Zn)　group. The rat diabetic models were made through intraperitoneal injection of streptozotocin(STZ) in STZ and STZ+Zn groups.The rats  in STZ+Zn and Zn groups were orally injected with 5 mg?kg-1of Zn sulphate twice a week. After fed for 16 weeks,the kidneys of  rats were obtained and  organ coefficient of kidney was calculated.The histopathological  changes of  kindeys  and the expressions of MMP-9,VEGF and MT in kidney tissues were detected with immunohistochemistry method. Results Compared with NC group,the organ coefficients  in STZ group and STZ+Zn group were increased (P< 0.05). Compared with STZ group,the organ coefficient in STZ+Zn group was increased(P<0.05). There was no difference of organ coefficient between STZ group and Zn group (P＞0.05).The MMP-9,VEGF, and MT expressed in kidneys of rats.MMP-9 and VEGF mainly expressed in the distal renal tubule;and MT mainly expressed in the proximal renal tubulei. there was no difference  of the expressions of MMP-9,VEGF, and MT in kidney tissues between various groups(P>0.05).Conclusion External Zn intervention can  increase the organ cofficient of kidney in diabetic rats,but dosen’t affect the organ coefficient of kindey in normal rats.  The expressions of  MMP-9,VEGF, and MT  in kidney tissues of  rats have no changes after external Zn intervention.

Key words: vascular endothelial growth factor;metallothionein, matrix metalloproteinase-9;Zn；diabetes mellitus,experime