The attenuation effect of 3,4-dihydroxy-phenyl lactic acid and salvianolic acid B on venular thrombosis induced in rat mesentery by photochemical reaction.

3,4-dihydroxy-phenyl lactic acid (DLA) and salvianolic acid B (SAB) are two major water-soluble components of Salvia miltiorrhiza (SM). Previous works have revealed the ability of DLA and SAB to scavenge oxygen free radicals, inhibiting the expression of adhesion molecules CD11b/CD18 in neutrophil. Cardiotonic pills (CP), which is a traditional Chinese medicine compound preparation containing DLA and SAB, was found to inhibit venular thrombosis induced by photochemical reaction (PR) in rat mesentery. The present study addressed the effect of DLA and SAB on PR-induced thrombosis in rat mesentery by utilizing a microcirculation dynamic viewing system. The result demonstrated that both DLA and SAB delayed thrombus-initiation time, while DLA also prolonged thrombus half-size time. The experiments explored the mechanism underlying that the dihydrorhodamine 123 (DHR) fluorescence in the mesenteric venular walls after PR challenge was diminished by pretreatment with either DLA or SAB, the expression of CD18 in neutrophils elicited by PR was depressed by administration of DLA, while mast cell degranulation in rat mesentery induced by PR was damped by SAB. The antioxidant potential of the two substances is likely to be responsible for their most beneficial effects on thrombosis, through either directly scavenging the peroxides produced and/or indirectly depressing the expression of adhesion molecules in neutrophil.

Improving effect of post-treatment with Panax notoginseng saponins on lipopolysaccharide-induced microcirculatory disturbance in rat mesentery.

Panax notoginseng saponin (PNS) is the collective of the major effective components of Panax notoginseng. The present study intended to explore the effect of post-treatment of PNS on rat mesentery microcirculatory disturbance induced by lipopolysaccharide (LPS) continuous challenge. By virtue of a microcirculation observation system, the vascular hemodynamics were determined continuously until 60 min of LPS (2 mg/kg/h) infusion through the left femoral vein. After observation, blood was taken for assessment of the expression of CD11b/CD18 in neutrophils and the concentration of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interferon-gamma (INF-gamma) in plasma with flow-cytometry. The number of leukocytes adherent to venular wall, the intensity of hydrogen peroxide dependent dihydrorhodamine 123 (DHR) fluorescence in the venular walls and albumin leakage from venules were increased impressively after 20 min of LPS infusion, the RBCs velocity diminished after 30 min, and degranulated mast cells increased remarkably after 60 min. Post-treatment with PNS (5 mg/kg/h) through the left jugular vein from 20 min of LPS exposure resulted in significant reduction in the number of adherent leukocytes, degranulation of mast cell, expression of CD11b and the concentration of IL-6, INF-gamma, while had no influence on the intensity of DHR fluorescence and albumin leakage. The results suggested that post-treatment with PNS significantly attenuated microcirculatory disturbance induced by LPS.

Effect of notoginsenoside R1 on hepatic microcirculation disturbance induced by gut ischemia and reperfusion.

AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated for 15 min to induce gut ischemia followed by 30-min reperfusion. In another set of experiments, R1 was continuously infused (10 mg/kg per hour) from 10 min before I/R until the end of the investigation to study the influence of R1 on hepatic microcirculatory disturbance induced by gut I/R. Hepatic microcirculation was observed by inverted microscopy, and the vascular diameter, red blood cell (RBC) velocity and sinusoid perfusion were estimated. Leukocyte rolling and adhesion were observed under a laser confocal microscope. Thirty and 60 min after reperfusion, lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate transaminase (AST) in peripheral blood were determined. The expression of adhesion molecules CD11b/CD18 in neutrophils and tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in plasma were evaluated by flow cytometry. E-selectin and intercellular adhesion molecule-1 (ICAM-1) in hepatic tissue were examined by immunofluorescence. RESULTS: After gut I/R, the diameters of terminal portal venules and central veins, RBC velocity and the number of perfused sinusoids were decreased, while the leukocyte rolling and adhesion, the expression of E-selectin in hepatic vessels and CD18 in neutrophils, IL-6, MCP-1, LDH, ALT and AST were increased. R1 treatment attenuated these alterations except for IL-6 and MCP-1. CONCLUSION: R1 prevents I/R-induced hepatic microcirculation disturbance and hepatocyte injury. The effect of R1 is related to its inhibition of leukocyte rolling and adhesion by inhibiting the expression of E-selectin in endothelium and CD18 in neutrophils.

Protective effects of ginsenoside Rb1, ginsenoside Rg1, and notoginsenoside R1 on lipopolysaccharide-induced microcirculatory disturbance in rat mesentery.

Ginsenoside Rb1 (Rb1), ginsenoside Rg1 (Rg1), and notoginsenoside R1 (R1) are major active components of Panax notoginseng, a Chinese herb that is widely used in traditional Chinese medicine to enhance blood circulation and dissipate blood stasis. To evaluate the effect of these saponins on microcirculatory disturbance induced by lipopolysaccharide (LPS), vascular hemodynamics in rat mesentery was observed continuously during their administration using an inverted microscope and a high speed video camera system. LPS administration decreased red blood cell velocity but Rb1, Rg1, and R1 attenuated this effect. LPS administration caused leukocyte adhesion to the venular wall, mast cell degranulation, and the release of cytokines. Rb1, Rg1, and R1 reduced the number of adherent leukocytes, and inhibited mast cell degranulation and cytokine elevation. In vitro experiments using flow cytometry further demonstrated that a) the LPS-enhanced expression of CD11b/CD18 by neutrophils was significantly depressed by Rb1 and R1, and b) hydrogen peroxide (H(2)O(2)) release from neutrophils in response to LPS stimulation was inhibited by treatment with Rg1 and R1. These results suggest that the protective effect of Rb1 and R1 against leukocyte adhesion elicited by LPS may be associated with their suppressive action on the expression of CD11b/CD18 by neutrophils. The protective effect against mast cell degranulation by Rb1 and R1, and the blunting of H(2)O(2) release from neutrophils by Rg1 and R1 suggest mechanistic diversity in the effects of Panax notoginseng saponins in the attenuation of microcirculatory disturbance induced by LPS.

Compound Danshen injection improves endotoxin-induced microcirculatory disturbance in rat mesentery.

AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. METHODS: LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation, such as diameters of arterioles and venules, velocity of RBCs in venules, leukocyte rolling, adhesion and emigration, free radicals released from post-capillary venules, FITC-albumin leakage and mast cell degranulation, were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile, the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils, and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. RESULTS: The continuous infusion with LPS resulted in a number of responses in microcirculation, including a significant increase in the positive region of venule stained with Monastral blue B, rolling and adhesion of leukocytes, production of oxygen radical in venular wall, albumin efflux and enhanced mast cell degranulation in vivo, all of which, except for the leukocyte rolling, were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils, and the expression of ICAM-1 in HUVECs were increased by exposure to LPS, and they were attenuated by compound Danshen injection. CONCLUSION: These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance.