Characteristic enhancement of blood pressure V-shaped waves in sinoaortic-denervated rats in a conscious and quiet state.

A hemodynamic feature of chronic sinoaortic-denervated (SAD) rats is the increase in blood pressure variability (BPV) without significant changes in the average level of blood pressure (BP). The current study was designed to investigate the changes in BP V-shaped waves (V waves) in SAD rats. Sprague-Dawley (SD) rats were divided into 2 groups: SAD rats and sham-operated rats (n=13). Hemodynamics measurements were obtained in conscious, freely moving rats, four weeks after sinoaortic denervation or sham operation. V wave indices were evaluated in rats in both conscious and quiet states. Additionally, normal and high BPV was simulated by the production of V waves with different amplitudes. The results showed that the V wave amplitude was dramatically increased, with a significantly prolonged duration and reduced frequency in SAD rats. V wave BPV in SAD rats was significantly increased, though BP remained unchanged. The twenty-four hour BPV in all rats was positively correlated with amplitude, duration time and V wave BPV and negatively correlated with frequency. The systolic BP spectral powers in the low frequency range (0.38-0.45 Hz) were significantly reduced in the V waves of SAD rats. Moreover, there was a remarkable increase in mean BPV and a normal mean BP after simulating high BPV in SAD rats. These results suggest that enhancement of V waves might be a waveform character of BP in SAD rats in both the conscious and quiet states. These types of V waves appear to be related to a depression of sympathetic regulation of BP induced by sinoaortic denervation.

Salvia Miltiorrhiza Bge.f.alba Ameliorates the Progression of Monocrotaline-Induced Pulmonary Hypertension by Protecting Endothelial Injury in Rats.

Pulmonary hypertension (PH) is a life-threatening disease that is characterized by elevated pulmonary blood pressure, abnormally thickened pulmonary arteries, and right ventricular hypertrophy. Monocrotaline (MCT) has been used to generate an experimental model of PH in rats, with PH initiated from injuries of lung vascular endothelium. Salvia Miltiorrhiza Bge.f.alba is a widely used traditional herb in China, known to exert protective effects on vascular endothelial cell injury in animal experiments. However, the role of Salvia Miltiorrhiza Bge.f.alba in PH remains unclear. Thus, we investigated the effects of the aqueous extract of Salvia Miltiorrhiza Bge.f.alba (AESM) on MCT-induced PH and explored the pertinent mechanism. PH was induced in rats by a single subcutaneous injection of MCT (60 mg/kg body weight). Low or high dose (4.6 g/kg or 14 g/kg body weight) of AESM was then administered orally for 21 days to PH rats. Hemodynamic study showed that AESM reduced mean pulmonary artery pressure and improved right ventricle function. Lung pathological analysis revealed that AESM reduced wall thickness and lumen stenosis of pulmonary vessels. Also AESM ameliorated right ventricular hypertrophy. Measurement of biochemical parameters indicated that AESM decreased endothelin-1 and thromboxane A2 in plasma and increased nitrogen monoxide and prostacyclin in the plasma and reduced the increase of transforming growth factor ß1 in lung tissue. Our results suggest that AESM may ameliorate the progression of MCT-induced PH in rats, at least in part by its protective effect on endothelial injury. Therefore, Salvia Miltiorrhiza Bge.f.alba could be useful in the treatment of PH.

[The study of the expression and the prognostic value of Survivin and Ki67 in pancreatic endocrine tumors].

OBJECTIVE: To explore the relationship between the expression of Survivin and Ki67 with prognosis of pancreatic endocrine tumors (PETs). METHODS: Immunohistochemistry for Survivin and Ki67 was performed in 25 cases of normal pancreatic tissues and 81 cases of PETs by tissue microarrays and to observe the expression and evaluate the relationship with prognosis. RESULTS: (1)The expression of Survivin and Ki67 in PETs was significantly higher than that in normal pancreatic tissues (P <0.01); (2)The expression of Survivin and Ki67 in PETs was correlated with tissue grading and the TNM-staging (P < 0.05), but not related with tumor size, location and functional status. In addition, the expression of nuclear Survivin was association with lymph node metastasis (P < 0.05). (3)The high expression of Ki67 was related with the expression of nuclear Survivin, but not related with the expression of cytoplasmic Survivin. CONCLUSION: Survivin and Ki67 were both expressed in PETs, which were closely related to the clinical pathological characteristics. They could be used as new indicators in the evaluation of prognosis of PETs. The expression of Survivin in nucleus had more diagnostic significance than that in cytoplasm, and that could be highly correlated with lymph node metastasis, which would be used as a new marker of poor prognosis.

Neuroprotective effects of an aqueous extract of Futokadsura stem in an Aß-induced Alzheimer's disease-like rat model.

Futokadsura stem has been traditionally used to dispel wind-damp obstruction syndrome manifested as painful and stiff joints, tendon and muscle spasms, lower back pain, painful knees and pain from external injury. An aqueous extract of Futokadsura stem has previously been found to have neuro-protective effects in vitro. In this study, we aimed to investigate if the Futokadsura stem extract could protect the neuron in the brain of an Aß-induced Alzheimer's Disease (AD)-like rat model by improving the learning and memory ability of the rats. Learning and memory ability of the rats were measured by the Morris water maze test. Neuronal morphology in the hippocampus was examined by HE staining. Expression levels of Aß, TNF-α, IL-6 and synaptophysin (SYP) were measured by immunofluorescence. Nitric oxide (NO) and nitric oxide synthase (NOS) levels were measured by NO and NOS detecting kit. We found that aqueous extract of Futokadsura stem alleviated Aß(25-35)-induced impairment of spatial learning and memory in the AD rats. Furthermore, the extract protected the neurons by decreasing the expression of Aß, TNF-α and IL-6 and the content of NO and NOS in the brain, and increasing the expression of SYP in the hippocampus. Our data indicated that aqueous extract of Futokadsura stem improved the learning and memory ability of AD rats. The neuro-protective effect was accomplished probably by depressing inflammation and oxidative stress in the brain.

Increased active von Willebrand factor during disease development in the aging diabetic patient population.

Type 2 diabetes is known to cause endothelial activation resulting in the secretion of von Willebrand factor (VWF). We have shown that levels of VWF in a glycoprotein Ib-binding conformation are increased in specific clinical settings. The aim of the current study is to investigate whether active VWF levels increase during aging and the development of diabetes within the population of patients suffering from type 2 diabetes. Patients and controls were divided into two groups based on age: older and younger than 60 years of age. VWF antigen, VWF propeptide, VWF activation factor and total active VWF were measured. Patients older than 60 years of age had increased levels of total active VWF, VWF activation factor and VWF propeptide compared to younger patients and controls. All measured VWF parameters were associated with age in diabetic patients. Total active VWF and VWF propeptide correlated with the period of being diagnosed with diabetes. Regression analyses showed that especially the VWF activation factor was strongly associated with diabetes in patients older than 60 years of age. In conclusion, we found that the conformation of VWF could be involved in the disease process of diabetes and that the VWF in a glycoprotein Ib-binding conformation could play a role as risk marker during the development of diabetes in combination with an increase in age. Our study shows that the active quality of VWF was more important than the quantity.

[Analysis of epidermal growth factor receptor expression and gene expression status in tissue microarray of cervical squamous cell carcinoma].

OBJECTIVE: To elucidate the protein expression and gene expression status and the relationship between epidermal growth factor receptor (EGFR) protein expression and EGFR gene status. METHODS: Tissue microarray containing 72 cervical squamous cell carcinoma tissues was constructed, and EGFR protein expression and gene status were evaluated by immunohistochemical and fluorescence in situ hybridization (FISH) techniques. RESULTS: Protein expression of EGFR: 69 of 72 cervical squamous cell carcinomas were observed. The results demonstrated it was significant association with invasion depth, lymph node metastasis and lymph-vessel invasion (χ(2) = 4.998, P < 0.05; χ(2) = 4.299, P < 0.05; χ(2) = 4.686, P < 0.05) in cervical squamous cell carcinomas. For FISH assessing EGFR gene, 64 of 72 carcinomas were observed; 7 of 64 cases showed EGFR gene amplification, and 25 disomy, 23 trisomy and 9 polysomy were detected. There were high levels of protein expression in all the EGFR gene amplification cases, and there were significant association between EGFR protein expression and the gene copy number (χ(2) = 13.564, P < 0.05). CONCLUSIONS: EGFR may participate in the occurrence, progression and metastasis of cervical squamous cell carcinoma. Overexpression of EGFR protein may result from gene amplification and gene copy number increases, which showed that EGFR gene expression status may be a more effective biological indicator of cervical squamous cell carcinoma targeted therapy.

Hydroxysafflor yellow A attenuates lymphostatic encephalopathy-induced brain injury in rats.

Hydroxysafflor yellow A (HSYA) is a main chemical component of the flower of Carthamus tinctorius. The present study investigated whether HSYA could attenuate brain injury induced by lymphostatic encephalopathy (LE). This was induced in adult male Wistar rats by cervical lymphatic blockade (CLB). Heart rate variability (HRV) was used as an indirect measurement of the regulatory function of the autonomic nervous system by recording the ECG signals from rats. It was shown that treatment with HSYA (5 mg/kg, i.p.) significantly alleviated the neurological deficits observed in rats with LE. Histological staining revealed that HSYA treatment attenuated LE-induced cell apoptosis in the rostral ventrolateral medullus (RVLM). Animals in the LE groups exhibited impaired regulatory roles of the autonomic nervous system in cardiovascular function, which was suppressed by pretreatment with HSYA. Additionally, HSYA administration significantly prevented the decrease of endothelial nitric oxide synthase (eNOS) mRNA and protein expression in the RVLM of rats with LE. These findings suggest that HSYA might provide neuroprotection against LE-induced brain injury and the associated functional alterations, which is likely regulated by the nitric oxide pathway.

HIF-1-α and survivin involved in the anti-apoptotic effect of 2ME2 after global ischemia in rats.

Survivin is an anti-apoptotic gene that decreases the apoptosis by depressing the expression of caspase-3. Hypoxia-inducible factor-1-alpha (HIF-1-alpha) is a transcription factor specifically activated by hypoxia. 2-methoxyestradiol (2ME2) is an estradiol derivative and a known HIF-1-alpha inhibitor. 2ME2 decreased apoptosis by inhibiting HIF-1-alpha. The aim of the present study was to investigate if survivin is involved in the anti-apoptotic effect of 2ME2. Male adult rats were used to make the global ischemia (GI) model. Ten minutes after GI, 2ME2 was injected intraperitoneally (16 mg/kg weight). Rats were killed at 6 hours, 12 hours, 24 hours, 48 hours, 96 hours, and 7 days. GI produced a marked increase in HIF-1-alpha expressions in the hippocampus at 6 hours and peaked at 48-96 hours. The expressions of survivin and caspase-3 were increased lightly in a similar time course. These molecular changes were accompanied by massive cell loss and apoptosis in the hippocampal regions. 2ME2 treatment reduced the expression of HIF-1-alpha, increased survivin expression, and decreased the expression of caspase-3. These results indicate that survivin and HIF-1-alpha were involved in the anti-apoptotic effect of 2ME2 treated following GI. 2ME2 may decrease the HIF-1-alpha expression, up-regulate the survivin expression, inhibit the expression of caspase-3, and finally reduce apoptosis after GI.

Protective effects of hydrogen-rich saline on monocrotaline-induced pulmonary hypertension in a rat model.

BACKGROUND: Hydrogen-rich saline has been reported to have antioxidant and anti-inflammatory effects and effectively protect against organ damage. Oxidative stress and inflammation contribute to the pathogenesis and/or development of pulmonary hypertension. In this study, we investigated the effects of hydrogen-rich saline on the prevention of pulmonary hypertension induced by monocrotaline in a rat model. METHODS: In male Sprague-Dawley rats, pulmonary hypertension was induced by subcutaneous administration of monocrotaline at a concentration of 6 mg/100 g body weight. Hydrogen-rich saline (5 ml/kg) or saline was administered intraperitoneally once daily for 2 or 3 weeks. Severity of pulmonary hypertension was assessed by hemodynamic index and histologic analysis. Malondialdehyde and 8-hydroxy-desoxyguanosine level, and superoxide dismutase activity were measured in the lung tissue and serum. Levels of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6) in serum were determined with enzyme-linked immunosorbent assay. RESULTS: Hydrogen-rich saline treatment improved hemodynamics and reversed right ventricular hypertrophy. It also decreased malondialdehyde and 8-hydroxy-desoxyguanosine levels, and increased superoxide dismutase activity in the lung tissue and serum, accompanied by a decrease in pro-inflammatory cytokines. CONCLUSIONS: These results suggest that hydrogen-rich saline ameliorates the progression of pulmonary hypertension induced by monocrotaline in rats, which may be associated with its antioxidant and anti-inflammatory effects.

Extract of Ginkgo biloba promotes the expression of VEGF following subarachnoid hemorrhage in rats.

The study aimed to investigate the effect of extract of Ginkgo biloba (EGb) on the expression of vascular endothelial growth factor (VEGF) after subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH, SAH, vehicle, EGb1 (low-dose), and EGb2 (high-dose) groups. VEGF mRNA and VEGF protein were measured from brain tissues. The expressions of VEGF mRNA in SAH and vehicle groups were enhanced 24 and 72 hr after the establishment of SAH. Increased VEGF positive cells were found in the brain tissues in SAH and vehicle groups. The expressions of VEGF mRNA and VEGF protein were further increased by the pretreatment of EGb. We concluded that EGb exerts protective effects on secondary cerebral ischemic injury after SAH via the promotion of the expression of VEGF.

Variations in blood pressure and heart rate in conscious rats with cervical lymphatic blockade.

The possible effects of cervical lymphatic blockade (CLB) on a series of parameters in conscious freely moving rats were analysed. Blood pressure (BP) and heart rate (HR) for conscious male Sprague-Dawley rats at 1, 3, 7, 11, 15 and 21 days after a CLB or a sham operation were monitored continuously for 24 hours with a computerized recording system. Since BP and HR were subjected to spontaneous variations, blood pressure variability (BPV) and heart rate variability (HRV) were expressed as the standard deviation of beat-to-beat BP and HR values. The baroreflex sensitivities (BRS) were determined by measuring the heart period (HP = 60,000/HR) prolongation in response to the elevation in BP induced by an intravenous administration of phenylephrine at 1, 7, 15 and 21 days after the CLB or sham operation. Compared with those in sham-operated rats, the values of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), HR and BRS in CLB rats were significantly lower, whereas the values of BPV and HRV were markedly raised in CLB rats at different time points. Furthermore, the impaired ultrastructure in the dorsomedial nucleus of the solitary tract (dmNTS) including degeneration, apoptosis and necrosis in neurons and gliacytes, were apparent from the 1st to 15th day but the changes were most significant at 7th day after CLB operation. Structural changes appeared to be closely related to functional changes of the dmNTS at each time point. Thus, in CLB conscious rats, a significant decline in blood pressure accompanied by dysfunction in its regulation might be due to the impaired structure in the dmNTS.

Salvianolic acid B inhibits platelet adhesion under conditions of flow by a mechanism involving the collagen receptor alpha2beta1.

Salvianolic acid B (SAB) is a component of Danshen, a herb widely used in Chinese medicine, and was previously shown to exert a number of biological activities including inhibition of platelet function, but the exact mechanisms involved are unclear. SAB dose-dependently inhibited platelet deposition from flowing, anticoagulated whole blood to immobilized collagen at both venous and arterial shear rate, whereas platelet deposition to immobilized fibrinogen was not affected. The inhibitory effect of SAB on platelet adhesion to collagen was independent of alphaIIbbeta3, since SAB still inhibited platelet deposition in the presence of a alphaIIbbeta3-blocking peptide. SAB inhibited static platelet adhesion to a synthetic peptide specific for the collagen receptor alpha2beta1, whereas platelet adhesion to a glycoprotein VI-specific peptide was not affected. SAB inhibited binding of an antibody against alpha2beta1 to platelets as studied by flow cytometry, and inhibited the interaction of soluble alpha2beta1 to immobilized collagen in a solid phase binding assay. These combined results indicate that SAB inhibits platelet adhesion to immobilized collagen by interfering with the collagen receptor alpha2beta1.

The influence of the pulsatility of the blood flow on the extent of platelet adhesion.

A new improved flow system was developed to study the influence of blood flow pulsatility on platelet adhesion on adhesive proteins and bio-medical materials. The pulsatility was introduced by changing the shear rate every 15 s in blood that was aspirated through a perfusion chamber by a syringe pump. The advantage of this new system is that it avoids system related platelet activation. At steady low shear rate (300/s) after 5 min a collagen type III surface was covered for 24.2+/-3.8% with platelets. At steady high shear rate (1300/s) platelet coverage to collagen was 48.8+/-6.8%. When pulsatility was introduced by changing the shear rate was every 15 s form 300/s to 1300/s and vice-versa, platelet coverage after 5 min was increased to 60.4+/-4.0% (p<0.001). After 5 min perfusion samples were taken from the perfusate and the extent of platelet activation was measured. The significant difference in surface expression of P-selectin on platelets is only seen when comparing pulse flow with control (no flow). We concluded that a significant increase in platelet activation during blood pulsatile flow compared with steady flow, which results in an increased platelet adhesion to collagen.

Effects of extract of ginkgo biloba on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in a rat model of subarachnoid haemorrhage.

The purpose of this study was to investigate in effect of extract of Ginkgo biloba (EGb) on cerebral blood perfusion in a subarachnoid haemorrhage (SAH) rat model. SAH lead to an increase in intracranial pressure and decrease in cranial perfusion pressure and regional cerebral blood flow in all groups. However, the intracranial pressure increases in EGb groups were less than that of the vehicle group (p < .01), whereas the reduction in cranial perfusion pressure and regional cerebral blood flow in the EGb group was less than that of the vehicle and SAH groups (p < .01). It was concluded that EGb attenuates the increase in intracranial pressure and reduction in cerebral blood perfusion after SAH.

Expression of the receptors of VEGF and the influence of extract of Ginkgo biloba after cisternal injection of autologus arterial hemolysate in rats.

The study was aimed to investigate the alterations of vascular endothelial growth factor (VEGF) receptors and the influence of extract of Ginkgo biloba (EGb) after subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH, SAH, vehicle, EGb1 (lower dose), and EGb2 (higher dose) groups. Autologus arterial hemolysate was injected into cisterna magna to induce SAH. The non-SAH rats received cisternal injection of saline instead. Rats underwent RT-PCR determination of one of the VEGF receptors flt-1mRNA, and immunohistochemistry for VEGF receptors Flt-1 and Flk-1. The results revealed that there was only slight expression of flt-1mRNA in the brain tissue in non-SAH rats. The expression in SAH group was enhanced 24 hours and 72 hours after cisternal injection. No Flt-1 and Flk-1 positive cell was observed in the brain in non-SAH group. A good few Flt-1 and Flk-1 positive cells were found in cortex and other regions of the brain in SAH group. The expression of flt-1mRNA, Flt-1 and Flk-1 proteins were increased by the use of two doses of EGb. It was concluded that the up-regulated expression of the two kinds of VEGF receptors may be an intrinsic protective mechanism in the process of SAH, which can be enhanced by EGb.

Changes of nitric oxide, oxide free radicals, and systolic arterial blood pressure in rats with experimental lymphatostatic encephalopathy.

The model of lymphatostatic encephalopathy was established by occluding and removing profound cervical nodes in rats, and the kinetic alteration of nitric oxide (NO), maleic dialdehyde (MDA), free radical scavenger (CuZn-SOD) and arterial systolic blood pressure were determined on different days after the blockage. The results showed that the level of NO significantly decreased at 1 day (P<0.05) and further decreased at 3, 5 and 7 day (P<0.01). The levels of MDA at 1, 3, 5 and 7 day significantly increased, but the contents of CuZn-SOD significantly decreased compared with the control (P<0.01). There was negative correlation between the levels of MDA and CuZn-SOD, but there was no relationship between MDA an NO. Arterial systolic blood pressure decreased progressively after cervical lymphatic blockage. The results showed that NO, oxide free radicals and the disturbances of the cardiovascular regulation may play important roles in lymphatostatic encephalopathy.

Effects of blockade of cerebral lymphatic drainage on regional cerebral blood flow and brain edema after subarachnoid hemorrhage.

The study was designed to observe the influence of blockade of cerebral lymphatic drainage on the regional cerebral blood flow (rCBF) and brain edema after experimental subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH, SAH, and SAH plus cervical lymphatic blockade (SAH + CLB) groups. Autologous arterial hemolysate was injected into rat's cisterna magna to induce SAH. The rCBF was recorded continuously by a laser Doppler flowmeter. Intracranial pressure (ICP) was also monitored. After 24 hours and 72 hours of SAH, the rats were sacrificed and the brain was harvested for water content detection. It was found that there was no obvious change of rCBF and brain water content during the experiment in non-SAH group. An immediate and persistent drop in rCBF was found in SAH group. The drop in rCBF was more obvious in SAH + CLB group. CLB also worsened the SAH-induced increase in ICP. The brain water content 24 hours and 72 hours after induction of SAH in SAH group increased significantly. CLB led to a further increase of brain water content. In conclusion, blockade of cerebral lymphatic drainage pathway deteriorates the secondary cerebral ischemia and brain edema after SAH.

Zinc protoporphyrin aggravates cerebral ischemic injury following experimental subarachnoid hemorrhage.

This study was aimed to evaluate the influence of an antagonist of heme oxygenase, zinc protoporphyrin IX (ZnPPIX), on the production of endogenous carbon monoxide (CO) and the secondary cerebral injury after subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH, SAH, and ZnPPIX groups. Autologus arterial hemolysate was injected into rat cisterna magna to induce SAH. CO and cyclic guanosine monophosphate (cGMP) levels in the brain, and lactate dehydrogenase (LDH) activity in serum were determined 24 hours and 72 hours after cisternal injection. It was found that 24 hours and 72 hours after SAH, the CO contents in SAH group were increased by 20.76% and 37.36%, respectively. CO content in ZnPPIX group was statistically lower than that in SAH group. No obvious change of cGMP content in SAH group was found. However, cGMP content in ZnPPIX group was lower than that in SAH group. Serum LDH activity increased significantly after induction of SAH. LDH activity in ZnPPIX group increased to a greater extent. It was concluded that ZnPPIX aggravates the cerebral injury secondary to experimental SAH by inhibiting the production of endogenous CO. The activation of HO/CO pathway is an intrinsic protective mechanism against cerebral ischemic injury after SAH.

Elevated plasma tissue-type plasminogen activator (t-PA) and soluble thrombomodulin in patients suffering from severe acute respiratory syndrome (SARS) as a possible index for prognosis and treatment strategy.

OBJECTIVE: To detect the presence of endothelial injury in patients with severe acute respiratory syndrome (SARS) via enhanced levels of tissue-type plasminogen activator (t-PA) and soluble thrombomodulin (sTM). METHODS: Case patients were from Xuanwu Hospital (Capital University of Medical Sciences, Beijing, China), and all of them met clinical criteria for SARS. Healthy controls were some of the hospital employees. Endothelial injury bio-markers tPA and sTM were detected by commercial ELISA-methods. RESULTS: Classic plasma markers of endothelial injury, tPA and sTM significantly elevated in SARS patients in comparison to controls [t-PA: 1.48 +/- 0.16 nmol/L versus 0.25 +/- 0.03 nmol/L (P<0.0001), and sTM: 0.26 +/- 0.06 nmol/L versus 0.14 +/- 0.02 nmol/L (P<0.05)]. The only patient who died had extremely high levels of these endothelial injury markers (t-PA: 2.77 nmol/L and sTM: 1.01 nmol/L). The likelihood ratio analysis indicated the excellent discriminating power for SARS at the optimal cut-point of 0.49 nmol/L for tPA and 0.20 nmol/L for sTM, respectively. Significant numerical correlations were found among these endothelial injury markers in SARS patients. The numerical coefficient of correlation Pearson r between t-PA and sTM was 0.5867 (P<0.05). CONCLUSION: Increased plasma concentrations of tPA and sTM in patients with SARS suggest the possibility of endothelial injury. SARS patients might need anticoagulant therapy or fibrinolytic therapy in order to reverse intraalveolar coagulation, microthrombi formation, alveolar and interstitial fibrin deposition. It may not only provide a useful treatment and prognostic index but also allow a further understanding of the pathological condition of the disease.