Magnesium lithospermate B improves renal hemodynamics and reduces renal oxygen consumption in 5/6th renal ablation/infarction rats.

BACKGROUND: Magnesium lithospermate B (MLB) can promote renal microcirculation. The aim of the current project was to study whether MLB improves renal hemodynamics, oxygen consumption and subsequently attenuates hypoxia in rats induced by 5/6th renal Ablation/Infarction(A/I). METHODS: Chronic renal failure (CRF) was induced in male SD rats by the 5/6 (A/I) surgery. 30 rats were randomly divided into three groups: sham group, 5/6 (A/I) + vehicle group (CRF group) and 5/6 (A/I) + MLB (CRF + MLB) group. 28 days after the surgery, rats were given with saline or 100 mg/kg MLB by i.p. injection for 8 weeks. The 24-h urinary protein (24hUp), serum creatinine (Scr), blood urine nitrogen (BUN), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. The protein expression of Fibronectin (FN), Collagen-I (Col-I), Connective Tissue Growth Factor(CTGF) and Interleukin-6 (IL-6) were measured by Western blot. Renal blood flow (RBF) and renal O2 consumption (QO2) indicated as sodium reabsorption (QO2/TNa) were detected before sacrifice. Renal hypoxia was assessed by measuring the protein expression of nNOS, HIF-1α and VEGF. RESULTS: MLB significantly reduced 24hUp, Scr, BUN, SBP and DBP levels in rats with CRF. The expression of FN, Col-I, CTGF and IL-6 were down-regulated by MLB treatment in rats with CRF. In comparison to sham operated rats, 5/6 (A/I) rats had significantly lower RBF, and MLB significantly increased RBF in rats with CRF. Moreover, QO2/TNa was higher in the CRF group as compared to that in the sham group, and it was significantly attenuated in the CRF + MLB group. MLB reversed the expression of nNOS (neuronal nitric oxide synthase), HIF-1α (hypoxia inducible factor-1) and VEGF in rats with CRF. CONCLUSIONS: MLB improves renal function, fibrosis and inflammation in CRF rats induced by 5/6 (A/I), which is probably related to the increase in RBF, reduction of oxygen consumption and attenuation of renal hypoxia in the remnant kidney with CRF.

Multi-residue determination of organophosphorus and organochlorine pesticides in environmental samples using solid-phase extraction with cigarette filter followed by gas chromatography-mass spectrometry.

A solid-phase extraction (SPE) method was developed to extract 14 pesticides simultaneously from environment samples using cigarette filter as the sorbent before gas chromatography-mass spectrometry (GC-MS) analysis. Parameters influencing the extraction efficiency, such as the sample loading flow rate, eluent and elution volume, were optimized. The optimum sample loading rate was 3 mL/min, and the retained compounds were eluted with 6 mL of eluent at 1 mL/min under vacuum. Good linearity was obtained for all the 14 pesticides (r(2) >0.99) from 0.1 to 20 µg/L for water and from 2 to 400 µg/kg for soil samples. The detection limits (signal-to-noise=3) of the proposed method ranged from 0.01 to 0.20 µg/L for water samples and from 0.42 to 6.95 µg/kg for soil samples. The developed method was successfully applied for determination of the analytes in real environmental samples, and the mean recoveries ranged from 76.4 to 103.7% for water samples and from 79.9 to 105.3% for soil samples with the precisions (relative standard deviation) between 2.0 and 13.6%.

[Effects of shenshuai II recipe on the protein expressions of Ang II and nNOS in chronic renal failure rats' nephridial tissue].

OBJECTIVE: To observe the effects of Shenshuai II Recipe (SSR) on the fibrosis of remnant nephridial tissue and expressions of Ang II and nNOS in the chronic renal failure (CRF) rats induced by 5/6 ablation/infarction (A/I), and to preliminarily investigate its mechanism of action. METHODS: Fifty-seven SD male rats were used to prepare the CRF rat model by means of 5/6 A/I. After modeling, they were randomly divided into the model group, the SSR group (2 mL SSR condensed decoction given by gastrogavage), and the Western medicine group (treated by 2 mL suspension of losartan potassium and fosinopril sodium given by gastrogavage), 15 rats in each group. Another 15 rats were recruited as the normal control group. Equal volume of pure water was given to rats in the normal control group and the model group. Relevant treatment was given to rats in each group once daily, for 60 successive days. The serum creatinine (SCr), blood urea nitrogen (BUN), and creatinine clearance rate (CCr) were detected. The expressions of angiotensin II (Ang II) and nervous system type nitric oxide synthase (nNOS) in the remnant renal cortex and the medulla were detected by Western blot. The pathomorphology of the nephridial tissue was observed. RESULTS: Compared with the normal control group, the levels of SCr and BUN increased (P<0.01) and the level of CCr decreased (P<0.01) in the model group, indicating a successful modeling. Compared with the same group before treatment, the levels of SCr and BUN decreased and the level of CCr increased in the SSR group and the Western medicine group (all P<0.01). Compared with the model group after treatment, the levels of SCr and BUN decreased, and the expression of Ang II in the medulla decreased in the SSR group and the Western medicine group (P<0.01, P<0.05). The levels of CCr and protein expressions of nNOS in the renal cortex and the medulla obviously increased in the SSR group and the Western medicine group (P<0.01, P<0.05). The pathology of the nephridial tissue showed that the pathological changes in the SSR group were obviously ameliorated, better than those of the model group. CONCLUSIONS: SSR could improve the renal function and relieve the renal interstitial fibrosis in the rats induced by 5/6 A/I. Its mechanism of action was possibly correlated with regulating the renal imbalanced Ang II and nNOS signal transduction pathway.