In order to investigate the effects and mechanisms of calcium dobesilate on renal lesions in experimental type 2 diabetic rats, dibetic rats were randomly divided into control group (group C) and experimental group (group D) treated with calcium dobesitate. The serum creatinine (Scr), protein kinase C (PKC), creatinine clearance (Ccr), transforming growth factor-beta₁ (TGF-β₁), type IV collagen were compared among the groups after 24 weeks. The renal tissues were observed under light microscopy and electron microscopy. The results showed that after 24 weeks, Scr, PKC, TGF-β₁ in group D were significantly lower than in group C, meanwhile, renal pathologic changes in group D were improved. Ccr had no difference between group C and group D. It was concluded that calcium dobesilate could ameliorate renal lesions in diabetic rats through inhibiting PKC and TGF-β₁

In order to explore the role of activator protein-1 (AP-1) in the transcription of interleukin-5 (IL-5) gene regulated by protein kinase C (PKC) signal in peripheral blood T lymphocytes from asthmatic patient, T lymphocytes were isolated and purified from peripheral blood of each asthmatic patient. The T lymphocytes were randomly divided into 4 groups: group A (blank control), group B (treated with PKC agonist phorbol 12-myristate 13-acetate (PMA)), Group C (treated with PMA and AP-1 cis-element decoy oligodeoxynucleotides (decoy ODNs)), and group D (treated with PMA and AP-1 mutant decoy ODNs). The ODNs were transfected into the T cells of group C and D by cation liposome respectively. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to assess IL-5 mRNA expression, and electrophoretic mobility shift assays (EMSA) for the activation of AP-1. The results showed that the activation of AP-1 (88 003. 58±1 626. 57) and the expression of IL-5 mRNA (0. 8300±0. 0294) in T lymphocytes stimulated with PMA were significantly higher than these in blank control (20 888. 47±1103. 56 and 0. 3050±0. 0208, respectively,P<0.01), while the indexes (23 219. 83±1 024. 86 and 0. 3425±0. 0171 respectively) of T lymphocytes stimulated with PMA and AP-1 decoy ODNs were significantly inhibited, as compared with group B (P<0.01). The indexes (87 107.41±1 342. 92 and 0. 8225±0 0222, respectively) in T lymphocytes stimulated with PMA and AP-1 mutant decoy ODNs did not exhibit significant changes, as compared with group B (P>0.05). The significant positive correlation was found between the activation of AP-1 and the expression of IL-5 mRNA (P<0.01). It was concluded that AP-1 might participate in the signal transduction of PKC-triggered transcription of IL-5 gene in asthmatic T lymphocytes. This suggests the activation of PKC/AP-1 signal transduction cascade of T lymphocytes may play an important role in the pathogenesis of asthma.

This experiment aimed to investigate the effect of adrenergic system in the subnucleus commissuriu of nucleus solitrius tractus (CNTS) on renal nerve discharges. Norepinephrine (NE) was microinjected into the CNTS of rabbits and mean arterial blood pressure (MAP) and renal nerve discharges (FRND) were synchronously recorded. The results indicated that (1) microinjection of norepinephine into the CNTS of rabbit could significantly attenuate the frequency of renal nerve discharge, and at the same time decrease markedly the mean arterial pressure. (2) Microinjection of 0.3 nmol yohimbin into CNTS had no significant influence on FRND and MAP, but could attenuate and even reverse the effects of NE on FRND and MAP. These results suggest that micro-injection of NE into CNTS may activate the alpha-adrenorecptor located in CNTS and secondarily produce a depressor effect by attenuating the activity of peripheral sympathetic nervous system.

The apoptosis and the expression of tumor suppressor gene p53 in hypercholesterolemia (HC)-induced renal injury were investigated in rats. A high cholesterol diet (HCD)-induced HC rat model was made and serum lipid, urinary protein excretion (UPE) and N-aceto-β-D-glucosidase (NAG) were measured. The levels of malondialdehyde (MDA), as an index of lipid peroxidation, in renal cortex and serum were compared between the two diet groups. Apoptosis and p53 expression were determined by TUNEL and immunohistochemistry, respectively. In the HCD-induced HC group, serum total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C) as well as triglyceride (TG) were significantly increased, while the level of high density lipoprotein-cholesterol (HDL-C) decreased. Meanwhile, increased excretions of UPE and NAG in urine were observed, which were accompanied with a decrease in urinary creatinine clearance (Ccr) and indicated both glomerular and tubular damages. In addition, apoptotic cell death coexisted in the kidney, as revealed by increased TUNEL positive cells. Finally, an increase in p53 expression was observed in tubuli, but not in glomeruli. Both TUNEL positive cells and p53 expression were found to be correlated to the level of renal cortical MDA (r=0.817,P<0.01 andr=0.547,P<0.01, respectively). The major manifestation of HCD-induced renal injury is apoptosis. The lipid peroxidation is a critical event to induce DNa damage and p53 is involved in the pathogenesis of lipid-induced renal injury.