Effect Of Tujian Decoction On Protein Kinase C In Diabetic Rat Renal Cortex

Objective:To investigate whether administration of Tujian decoction (Chinese herbal medicine) influences renal protein kinase C(PKC) activity and expression of PKC β isoforms in diabetic rat. Methods:Experimental diabetic nephropathy model was induced by nephrectomy combined with streptozotocin (STZ) injection in Sprague-Dawley rat There were 5 groups in this study: normal control rats (group NC, n=8), nephrectomy control rats(group QC, n=8), diabetic nephrectomized control rats ( group DM, n=8), diabetic nephrectomized control rats treated with Tujian decoction (group ZY, n=8) and diabetic nephrectomized control rats treated with Valsartan (group VT, n=8). Tujian decoction (20 g ·kg^-1· d^-1) and Valsartan (20mg·kg^-1·d^-1) were orally administrated respectively in group VT and ZY for 12 weeks. All rats sacrificed at the end of the 12th week, 24 hours urine protein excretion was detected, the morphologic changes in rugular pathological section were observed, and the mesangium and basement membrane area in PAS stain section per glomerular tuft area were calculated by computer-assisted image analysis system. The PKC activity was measured by [³H]phorbol 12,13-dibutyrate([³H] PDBu) binding assay. The expression of PKC α, βⅠ and βⅡ isoforms in glomerulus was assessed by immunohistochemistry. The expression of PKC βⅠ and β â…¡ isoforms in renal cotex was analysised by immunoblotting. Results:At 12 weeks following STZ injection, the 24 hours urine protein excretion in DM group rats was significant higher than NC and QC group. Diffuse increasing width of mesangial area without cellular proliferation and increasing extracellular matrix (ECM) in glomeruli were observed in DM group rats. The mesangium and basement membrane area per glomerulus in PAS stain section per glomerular tuft were markedly increased in DM group than in NC and QC group (P<0.01). The amount of...