Abstract:Aim To compare and contrast two kinds of abdominal aortic aneurysm(AAA) model of rats, and thus to establish the foundation for the further study of AAA in vivo. Methods Commercially available porcine pancreatic elastase was Infused into the SD rat abdominal aorta, or orthotopic engraftment of guinea pig aorta was transplanted into the SD rat abdominal aorta. The patency, and macroscopic, microscopic morphologic and matrix metalloproteinase(MMP) changes that occurred in xenografts and the controls were compared postoperative 2 weeks or 4 weeks. Results There were AAA formation in 64 percent infused rats and 88 percent transplanted rats, without haemorrhage and intraluminal thrombus. In comparison to the AAA induced by elastase, the lesions of AAA walls after xenograft were more serious and the expression of MMP-2 and MMP-9 were remarkably increased. Conclusions Both of the methods may induce AAA,but xenograft model has higher stability and reliability.

Abstract:Aim To assess the corelation between vascular smooth muscle cell proliferation and apoptosis, under the regulation of cell cycle, during abdominal aortic aneurysm formation and development. Methods Guinea pig-SD rat abdominal aorta xenografts were used as experimental model. Immunohistochemistry and in situ end-labeling of DNA fragments determined vascular smooth muscle cell and their proliferation and apoptosis. Cell proliferation and apoptosis index were counted with the use of computer-generated image analysis at 1,2,3,4 week after transplantation. Results Graft dilation, during 1-2 weeks, were moderate, but marked in the later 2 weeks in comparison to the controls. Vascular smooth muscle cell proliferation proceeds apoptosis by 2 weeks, and shifts to the contrary in another 2 weeks. The abdominal aortic diameter had a significant correlation with increasing vascular smooth muscle cell apoptosis in xenograft. Conclusion vascular smooth muscle cell proliferation and apoptosis is connected with abdominal aortic structure damage and remodeling, whose imbalance contributes to abdominal aortic aneurysm formation and development.

Abstract:Aim To observe the effects of API0134 on arterial thrombus formation and exploring the mechanism of anti-platelet aggregation. Methods An thrombus model of rabbits with high cholesterolemia was established; and the platelet aggregation function, intracellular ionized calcium i, intracellular ionized magnesium i, cAMP, cGMP and inositol trisphosphate (IP 3) in platelet were examined with Flow cytometer, radioimmunoassay, inositol incoporation and so on. Results The occlusive thrombus formation time was lengthened and the platelet aggregation was inhibited significantly in API0134 group compared with model group. Meanwhile, the increase of platelet concentration of i, i, IP 3 in platelet induced by the thrombus formation were inhibited, and the cAMP concentration in platelet was increased markedly in API0134 treated group compared with control group. Conclusions API0134 exerts strong anti-thrombus and anti-platelet aggregation effects. The mechanism of anti-platelet aggregation is closely related to regulating the balance of intracellular i, i, cAMP and IP 3 in platelet.

Abstract:Aim To assess the response of adventitia and adventitial cells after arterial injury. Methods Newzealand rabbits underwent balloon injury to the abdominal artery by over-sized angioplasty balloon. Adventitial changes were characterized by histochemistry, morphometry, immunohistochemistry and transmission electron microscope. Results Adventitial thickness significantly increased at all time points comparing with normal vessels. Cell density reached the maximum level at 7 d, whereas at l4 d, the cell density reverted toward the baseline. Meanwhile, the cell proliferation index rapidly increased at 3 d and 7 d respectively, and it reduced to normal level at 14 d. At 7 and 14 days after injury, The adventitia exhibited weakly positive staining for actin at 3 days, and strongly positive at 7 and 14 days. Adventitial cells displayed numerous actin microfilaments and marked dilated rough endoplasmic reticulum at 7 and 14 days after injury. Conclusions This study demonstrated the involvement of the adventitia in vascular repair process. The hypercellularity of the adventitial layer, proliferation fibroblast, and modulation of their phenotype to myofibroblast are associated with the thickness of adventitia.

Abstract:Aim To explore whether the autocrine and paracrine secretion of the damaged endothelial cells (EC) can regulate the damaged EC and the effect of hypothalamus-pituitary neuroendocrine axis on the autocrine and paracrine secretion of the damaged EC. The changes in the metabolism of lipid peroxide (LPO) and the expression of inducible nitric oxide synthase (iNOS) were detected through the influence of conditioned media of endothelial cells (EC-CM) induced by diamide and affected by hypothalamus-pituitary cells on injured EC respectively. Methods The normal EC-CM was used in the control group. In the experimental group, the EC-CM induced by diamide and the EC-CM induced by both conditioned medium of hypothalamus-pituitary cells and diamide were prepared. The EC injured by diamide were cultured respectively with the above three EC-CM. After culturing with the three EC-CM, all EC of the experimental and control groups were cultured in serum-free medium. Then the supernatant of the above serum-free media and cultured EC were collected for detecting the content of LPO and iNOS. Results It was shown the EC-CM induced by diamide and the EC-CM induced by both conditioned medium of hypothalamus-pituitary cells and diamide had down regulative effect on the metabolism of LPO and up regulative effect on iNOS expression of injured EC. However, the medium containing hypothalamus-pituitary tissue showed more intensive anti-lipid peroxidation effect. Conclusion It is suggested that when EC was damaged by diamide, its autocrine and paracrine secretion can regulate its LPO metabolism down and regulate its iNOS expression up, which might be one of the mechanisms in EC for defending against external injury.

Abstract:Aim To ascertain whether Dimethylsulfoxide (DMSO)-soluble particles from cigarette smoke (DSP) stimulate the proliferation of vascular smooth muscle cells (VSMC). Methods Rabbit aortic vascular smooth muscle cells were used as target cell. The proliferation of VSMC was assayed by the measurement of MTT and flow cytometry. Cellular protein assay (ELISA) was used to observe the change of protein content. The amount of endothelin-1 (ET-1) secreted by VSMC was measured by radioimmunoassay (RIA). Results In contrast to the control group (without DSP), protein absorbance of VAMC added 1∶1000, 2∶1000 and 3∶1000 DSP did not make significant difference (p>0.05). VSMC added 1∶1000 and 2∶1000 DSP showed proliferation significantly (p<0.01), and yet 3∶1000 DSP group did not. The amount of ET-1 in the medium of DSP groups were significantly increased, especially in 2∶1000 DSP group (p<0.01) and the result of flow cytometry showed that in 2∶1000 DSP group, the cell numbers of G 1 phase were decreased and cell numbers of S phase were increased markedly (p<0.01). Conclusion 1∶1000 and 2∶1000 DSP can stimulate significantly the proliferation of VSMC, and ET-1 produced by VSMC may play an important role in the proliferation of VSMC.

Abstract:Aim To investigate mechanism for accelerated atherosclerosis in diabetic patients, advanced glycosylation end products (AGE) on the expression of monocyte chemoattractant protein-1 (MCP-1) mRNA in cultured aortic smooth muscle cells (SMC) of rat was observed. Methods SMC were isolated and cultured from the thoracic aorta of rat, then were exposed to AGE-BSA of 200 mg/L (glycated with glucose of 0, 5, 20, 50, and 80 mmol/L) for 24 h, exposed to AGE-BSA of 200 mg/L (glycated with glucose of 50 mmol/L) for 0, 12, 24, and 36 h. Expression of MCP-1 was quantified by RT-PCR with α-actin as internal standard. Results The expression of MCP-1 mRNA were increased by AGE-BSA incubated with glucose concentration of 20, 50, 80 mmol/L (p<0.005), respectively. After intervention of AGE-BSA for periods of 12, 24 and 36 h, MCP-1 expression was increased markedly (p<0.001). Conclusion AGEs increased the expression of MCP-1 mRNA in aortic smooth muscle cells of rats.

Abstract:Aim To Investigate whether activate lymphocyte contact induces the expression of matrix metalloproteinases in vascular smooth muscle cells. Methods The healthy human peripheral blood lymphocytes, which were activated by incubating with PMA and then fixed in 1% paraformaldehyde, were incubated with cultured human fetal aortic vascular smooth muscle cells (hVSMC). The gelatinase (MMP-2 and MMP-9) and stromelysin (MMP-3) activity in conditioned culture media were demonstrated by gelatin SDS-PAGE and casein SDS-PAGE. Results Unstimulated cultured hVSMC constitutively express 72 kDa zymogen of MMP-2 (pro-MMP-2) with a little of 66 kDa activated MMP-2, and no MMP-1, MMP-3, MMP-9 were detected by SDS-PAGE. After incubating with PMA-stimulated lymphocytes for 24 hours, zymography showed the MMP-1, MMP-3 and MMP-9 activity in the conditioned culture media, and activated MMP-2 increased 198%±27% compared with the control group (p<0.01). The unstimulated lymphocytes had no effect on MMPs synthesis of human fetal aortic vascular smooth muscle cells and PMA-activated lymphocyte had no gelatinolytic and caseinolytic activity on its own. Conclusions Activated lymphocytes may play an important role in atherosclerotic plaque repture through inducing vascular smooth cells to produce increased MMP and activate MMP-2.

Abstract:Aim To investigate the relationship between endothelium dependent vascular relaxation (EDVR) and endothelin at different stages of rats with non-insulin-dependent diabetes mellitus (NIDDM). Methods The rat models of NIDDM were made. At 10 and 25 weeks after injecting STZ, the contents of plasma endothelin were measured respectively with radioimmunoassay, and EDVR actions were studied by isometric tension recording in the isolated aorta rings. Results At 10 weeks of NIDDM rats, the EDVR responses of aortae were obviously weakened and the level of plasma markedly ascended, comparing with normal placebo group. At 25 weeks of NIDDM rats, the EDVR respondes of aortae were further imparired, but the level of plasma endothelin descended and was lower than the NIDDM rats of 10 weeks (p<0.05). Conclusions The results suggest that weakened EDVR may be related to the increased content of endothelin at early stage of NIDDM rat, but impaired EDVR may have nothing to do with endothelin at late period.

Abstract:Aim The effects of in vivo administration of human high density lipoprotein (HDL) injection on the development of aortic streaks were studied in cholesterol-fed rabbits. Methods The rabbits received a 1% cholesterol-rich diet for 8 weeks. During this period, the HDL group was intravenously administered with 50 mg/week of HDL injection; the lovastatin group was administered with 10 mg/day of lovastatin via subcutaneous injection; the placebo group received normal saline (0.9% NaCl). The HDL injection was manufactured and provided by Tsinghua Unisplendour Guhan Bio-pharmaceutical Corporation Ltd. During the study, plasma lipid levels followed a similar profile in all groups to cholesterol-rich diet. Results At the completion of study, atherosclerotic-like lipid-rich lesions covered 32.6%±21.7% (x±s), of the intima aortic surface in the placebo group, 9.1%±7.8% in the HDL group, and 20.8%±13.1% in the lovastatin group. The levels of plasma total cholesterol were 10.05±2.30, 2.93±1.41, and 3.74±1.73 g/L in placebo, HDL, and lovastatin groups, respectively. The levels of plasma high density lipoprotein cholesterol (HDLC)were 0.43±0.12, 0.62±0.23, 0.23±0.14 g/L in placebo, HDL, and lovastatin groups, respectively. The value of total cholesterol deposited within vessel wall were significantly lower in the aortas of the HDL group than those in the placebo group and lovastatin group. Human HDL injection showed a more efficient inhibition of atherosclerotic lesions than lovastatin did. Conclusion The administration of human HDL injection to cholesterol-fed rabbits dramatically inhibits the extent of aortic fatty streaks, modifies plasma lipid, and lipid deposition in the arterial wall.

Abstract:Aim In order to study the relationship bewteen activity of NF-κB and the expressions of monocyte chemotactic protein-1 (MCP-1) and protein kinase C (PKCα) and atherosclerosis (As) plaques of different stages. Methods Using electrophoretic mobility shift assay (EMSA), immunohistochemitry and in situ hybridyzation,We study activity of NF-κB and the expressions of monocyte chemotactic protein-1 (MCP-1) and protein kinase C (PKCα) varied in atherosclerosis (As)plaques of different stages. Results The resultes confirmed that the activity of NF-κB as well as the expressions of monocyte chemotactic protein-1 (MCP-1) and protein kinase C (PKCα) in As plaque was increased in a time dependent manner as compared with those in control group (p<0.05). Which was consistent with the increaceing of activity of NF-κB and up-regulated in the expressions of MCP-1and PKCα. Conclusion All of these indicated that NF-κB activation, the up-regulated expressions of MCP-1and PKCα may take part in pathogenesis and development of As.

Abstract:Aim To investigate the high level expression of human phospholipid transfer protein in the yeast pichia pastoris. Methods Total RNA was prepared from Chinese fetal liver tissue, cDNA fragment encoding human phospholipid transfer protein was amplified by reverse transcriptase polymerase chain reaction using specific primers, and then was integrated into the chromosomes of pichia pastoris GS115 via homologous recombination. Recombinant human phospholipid transfer protein was expressed under the control of the promoter of the alcohol oxidase gene(AOX1) and was detected by SDS-PAGE. Results Five recombinant colony among 20 colonies grown poorly on MM plates was selected which highly expressed human phospholipid transfer protein. The molecular weight of recombinant phospholipid transfer protein was estimated about 75 kDa analyzed by SDS-PAGE. Conclusions Human phospholipid transfer protein can be high level expressed in the yeast pichia pastoris and the secreted recombinant human phospholipid transfer protein was in the form of the glycosylated monomer.

Abstract:Aim To evaluate the effect of lipopolysaccharide on human monocytes tumor necrosis factor α production and nuclear factor kappa B activation. Methods Monocytes were isolated by Ficoll density gradient from blood of healthy volunteers. The amount of tumor necrosis factor α protein in culture medium was quantified by using tumor necrosis factor α ELISA systems. Nuclear factor kappa B translocation in monocytes was observed by immunohistochemistry assay. Results We find that nuclear factor kappa B was activated after being stimulated for 15 minutes and reached peak at 1 hour. Lipopolysaccharide (1 μg/L～1 mg/L) induced monocytes tumor necrosis factor α production in a dose-dependent manner. Tumor necrosis factor α protein in medium could be detected at 1 hours, and achieve peak at 6 hour. Nuclear factor kappa B activation before tumor necrosis factor α production in monocytes. Conclusions Lipopolysaccharide induced pro-inflammation cytokine production at least in part through nuclear factor kappa B activation in monocytes.

Abstract:Aim To investigate the effects of homocysteine on the lectin-like oxidized low density lipoprotein receptor (LOX-1) mRNA expression and uptake of ox-LDL in cultured human umbilical vein endothelial cells (hUVEC). Methods Total RNA was extracted with Trizol reagent. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to quantify mRNA expression of LOX-1 genein hUVECs. ox-LDL was radioiodinated with 125 I to detect the uptake of ox-LDL by hUVEC. Results LOX-1 mRNA expression increased after cells were incubated with increasing concentration of homocycteine (0.1, 1, 10 mmol/L) for 48 hours. The uptake of ox-LDL by hUVEC increased at the same time. Conclusion Homocysteine increases the expression of LOX-1 mRNA in hUVEC and uptake of ox-LDL by them which may contribute to the proatherogenic potential of homocysteine.

Abstract:Aim To study the mechanism of Qing Yuan Tiao Zhi Capsule (QYTZC)decreasing blood-fat at the molecular level. Methods 27 Wistar rats were randomly divided into normal group (n=9), hyperlipemia group (n=9) and treatment group (n=9). In the experiment, all the rats from both hyperlipemia group and treatment group were daily fed with high fat feed for 8 days,with no limit to drinking except those from normal group, which were fed with ordinary feed. The rats in treatment group were given QYTZC (3 pellets for each, dissolved in water of 5 mL)by perfusion, twice a day after a week of the modeling. After the experiment, low density lipoprotein receptor (LDLR) mRNA was detected in the hepatic tissues of the rats from each group by reverse transcriptase-polymerase chain reaction (RT-PCR). Results QYTZC had a significant effect on LDLR gene expression of the rat (p<0.001). Conclusions QYTZC could increase LDLR gene expressin in rat hepatic tissues and, thus, decrease the level of blood-fat.

Abstract:Aim To observe the effects of angiotensin Ⅱ 1 receptor antagonist Losartan on coronary and systemic hemodynamics in the normotensive and renovascular hypertension rats. Methods Coronary blood flow (CBF) intra-arterial blood pressure, heart rate, and coronary vascular resistance (CVR) were measured at rest, during isometric exercise before and 60 min after Losartan (25 mg/kg, ig). Results The drug induced a prompt, significant decrease in mean arterial pressure (MAP) and a sustained increase in CBF, but no effects to normotensive rats. Conclusions These observations suggest that angiotensin Ⅱ maintains the ability to alter the control mechanisms of CBF even under long-term conditions and that Losartan reverses the angiotensin Ⅱ-induced effects on coronary hemodynamic.

Abstract:Aim To investigate the clinical significance of reciprocal ST-segment changes during acute myocardial infarction. Methods The clinical and electrocardiographic data were analyzed and compared with results of coronary angiography in 166 patients with first acute myocardial infarction (AMI). Results Compared with the patients without precordial ST- segment change, the level of creatine kinase, the incidence of arrhythmia and heart failure as the complications of acute myocardial infarction and the percentage of lesions in left anterior descending artery (LAD) and multiple coronary vessels were significantly higher, the level of left ventricular ejection fraction was significantly lower in patients with precordial V 4～V 6 ST-segment depression during inferior acute myocardial infarction. On the other hand, the incidence of proximal lesion in LAD as the infarct-related artery was significantly higher in patients with inferior ST-segment depression than those without in anterior acute myocardial infarction, whereas the creatine kinase level, left ventricular ejection fraction and incidence of acute myocardial infarction complication were not significantly different between the two groups. Conclusions Precordial V 4～V 6 ST- segment depression during early inferior acute myocardial infarction may indicate larger inferior infarct, or accompanying disease of LAD or multiple coronary vessels. Anterior acute myocardial infarction complicated inferior ST-segment depression may suggest proximal lesion in LAD, which is an indication for early reperfusion therapy.

Abstract:Aim To explore the change of serum insulin-like growth factor-1 and insulin-like growth factor binding protein-3 and their values of clinic. Methods Serum levels of insulin-like growth factor-1 and insulin-like growth factor binding protein-3 in sixty cases of acute cerebral infarction(the third day and the fourteenth day)and thirty cases of healthy subjects were measured with two-layer antibody sandwich ELISA. Then analyse the different between the patient and the normal controls. According to the diameter of infarction in the CT or MRI imagines, the patients were divided into three groups: large infarction (diameter≥5 cm), middle infarction(1.5 cm≤diameter<5 cm)and small infarction(diameter<1.5 cm). Then analyze the relation between the range of the infarction and the levels of IGF-1 and IGFBP-3 in the serum. Results Serum IGF-1 and IGFBP-3 levels of the patients(the third day and the fourteenth day)are much lower than those of healthy control groups (p<0.001). Serum IGF-1 and IGFBP-3 levels of the patients at the third day are much lower than that at the fourteenth day(p<0.05). The levels of different infarction groups are quite different(p<0.001). Conclusions Therefore serum IGF-1 may play a role in protecting the nerve cell in the area of infarction,and the range of the infarction may affect the serum levels of IGF-1 and IGFBP-3.

Abstract:Aim To observe serum PON-1 activity in patient with acute coronary syndrome(ACS)and investigate its role in acute coronary syndrome. Methods Serum PON-1 activity was assessed by use of phenylacetate(arylesterase) as substrate. PON-1 activity of 40 patients with acute coronary syndrome, 32 patients with stable coronary heart disease(SCHD) and 24 controls were determined by the use of a recording spectrophotometer. Results In patients with acute myocardial infarctioon(AMI) and unstable agina pectoris(UAP),serum PON-1 activity[95±42 μmol/(L·min), 80±36 μmol/(L·min), respectively] were significantly lower(p<0.05) than those in patients with SCHD [133±29 μmol/(L·min)] and controls [136±64 μmol/(L·min)];there was no difference between SCHD group and controls. Serum PON-1 activity was positively correlated with serum triglyceride levels(r=0.496, P=0.001) and with ApoB(r=0.342, P=0.002),but serum PON-1 activity was not correlated with high density lipoprotein cholesterol(HDLC). Conclusions The low serum PON-1 activity in patients with ACS indicated the reduction of antioxidant properties may involve in the production of ACS.

Abstract:Aim To investigate the effects of homocysteine on cholesterol and carotid atherosclerotic plaque in patients with cerebral apoplexy induced by hypertension. Methods 149 patients were selected and divided into two groups: 74 patients with hypertension and cerebral apoplexy; 75 patients only with hypertension. The homocysteine(HCY) and cholesterol(TC) level of all these patients were assessed, and at the same time the ultrasound of carotid artery were performed. Results Hypertension with cerebral apoplexy HCY increased more significantly than patients with only hypertension (p<0.05). The incidence of carotid atherosclerotic plaque development in hypertension with cerebral apoplexy was much higher than patients with only hypertension(p<0.05). Conclusions The impair of the artery wall induced by hypertension and higher blood cholesterol were aggravated by hyperhomocysteine which also enhanced the development of cerebral apoplexy. The occurrence of cerebral apoplexy is the results of homocysteine, arteriosclerosis and higher cholesterol.

Abstract:Aim To study clinical features and connection in cerebrovascular disease incorporated gout. Methods We retrospective investigated 376 with stroke patients and 150 cases gout patients from February 1998 to May 2000. All patients were admitted to the medicine treatment and were examined by brain CT or MRI, biochemical and serological assessment. Results There were fifteen cases with cerebrovascular disease incorporated gout, fourteen were male, one case female. The average age was 69.3 years. Nine patients were infarcted brain, four patients were transient ischemic attack (TIA) and two patients were hemorrhage, another four patients were recurrent stroke. Conclusions Stroke incorporated gout is higher in foreland and male. Ischemic strokes were higher. They were usually associated with hypertension, heart disease, diabetes and high serum cholesterol. Stroke attack was linked with acute gout attack. Gout is probably the main risk factor for cerebrovascular disease in foreland and male.