OBJECTIVE: To investigate the effect of Yiqi Wenyang Huoxue Huatan Fang (YWHHF) on alleviating hypoxia-hypercarbia pulmonary hypertension by inhibiting endothelial-mesenchymal transition (EndoMT) BMP-7/Smads pathway. METHODS: Fifty male healthy SD rats of clean grede, weighting (180~220) g, were randomly divided into 5 groups (=10):normoxia group (N), hypoxia-hypercarbia group (HH); YWHHF high dose group (YH), middle dose group (YM) and low dose group (YL). The rats in N group were kept in normal oxygen environment, the remaining four groups were intermittently exposed to hypoxia-hypercarbia environment (9%~11% O, 5%~6% CO) for 4 weeks, 6 days a week, 8 hours per day. The rats in YH, YM, YL groups were received YWHHF gavage in a dosageof 0.6, 0.3, 0.15g/kg respectively (3 ml/kg),the rats in N and HH groups were received equal volume of normal saline. After 4 weeks, the mean pulmonary arterial pressure(mPAP) was detected,the right ventricular free wall and left ventricle plus ventricular septum were isolated to determine the right ventricular hypertrophy index. Lung ultrastructural changes were surveyed under an electronic microscopy, the changes of pulmonary artery structure surveyed by immunofluorescence, the mRNA levels of alpha-smooth muscle actin (α-SMA)、platelet endothelial cell adhesion molecule-1 (CD31)、bone morphogenetic protein-7 (BMP-7)、drosophila mothers against decapentaplegic protein1/5/8 (Smad1/5/8) were detected by RT-PCR, and the protein levels of α-SMA、CD31、BMP-7、p-Smad1/5/8 and Smad1/5/8 were detected by Western blot. RESULTS: Compared with N group, mPAP and the right ventricular hypertrophy index were increased,some significant injuries also were discovered under microscopic observation,the mRNA and protein expression of α-SMA was increased, and the mRNA expressions of CD31、BMP-7、Smad1/5/8 were decreased in the other four groups, the protein expressions of CD31、BMP-7、p-Smad1/5/8 were decreased(<0.05). Compared with HH group, the above changes in YH、YM、YL groups were all improved (<0.05). CONCLUSIONS YWHHF can inhibit EndoMT to alleviate pulmonary hypertension, and the mechanism may be related to the promotion of the expression of BMP-7/Smads pathway.
Animals ; Hypercapnia ; Hypertension, Pulmonary ; chemically induced ; Hypoxia ; Male ; Pulmonary Artery ; Rats ; Rats, Sprague-Dawley

Animals ; Hypertension, Pulmonary ; chemically induced ; physiopathology ; Monocrotaline ; adverse effects ; Rats ; Rats, Sprague-Dawley ; Thrombomodulin ; metabolism

OBJECTIVETo observe the changes in pulmonary artery protein kinase C (PKC) activity in rats with chronic inflammatory pulmonary hypertension (PHT).

METHODSChronic inflammatory PHT was induced in rats with monocrotaline. The PKC activities in the rat pulmonary arteries were measured by radioactive assay during the development of PHT.

RESULTSWith the development of chronic inflammatory PHT, the total and cytosolic fractions of PKC activity in PHT rat pulmonary arteries increased initially with subsequent decrease (Plt;0.05), but the membranous fraction of PKC activity and the membrane-to-cytosol PKC activity ratio increased continuously (P<0.05).

CONCLUSIONThe up-regulation of PKC activity and the translocation of PKC might be associated with the development of chronic inflammatory PHT in rats.

Animals ; Chronic Disease ; Hypertension, Pulmonary ; chemically induced ; enzymology ; Inflammation ; chemically induced ; enzymology ; Male ; Monocrotaline ; Protein Kinase C ; metabolism ; Pulmonary Artery ; enzymology ; Rats ; Rats, Wistar

In this study, we used a rat model of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) to investigate the role and mechanism of angiotensin (Ang)-(1-7) in regulating pulmonary artery diastolic function. Three weeks after subcutaneous injection of MCT or normal saline, the right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVHI) of rats were detected using a right heart catheter. Vascular endothelium-dependent relaxation was evaluated by acetylcholine (ACh)-induced vasodilation. The relaxation function of vascular smooth muscle was evaluated by sodium nitroprusside (SNP)-induced vasodilation. Human pulmonary artery endothelial cells (HPAECs) were incubated with Ang-(1-7) to measure nitric oxide (NO) release levels. The results showed that compared with control rats, RVSP and RVHI were significantly increased in the MCT-PAH rats, and both ACh or SNP-induced vasodilation were worsened. Incubation of pulmonary artery of MCT-PAH rats with Ang-(1-7) (1 × 10^-9-1 × 10^-4 mol/L) caused significant vaso-relaxation. Pre-incubation of Ang-(1-7) in the pulmonary artery of MCT-PAH rats significantly improved ACh-induced endothelium-dependent relaxation, but had no significant effect on SNP-induced endothelium-independent relaxation. In addition, Ang-(1-7) treatment significantly increased NO levels in HPAECs. The Mas receptor antagonist A-779 inhibited the effects of Ang-(1-7) on endothelium-dependent relaxation and NO release from endothelial cells. The above results demonstrate that Ang-(1-7) promotes the release of NO from endothelial cells by activating Mas receptor, thereby improving the endothelium-dependent relaxation function of PAH pulmonary arteries.
Rats ; Humans ; Animals ; Vasodilation ; Pulmonary Arterial Hypertension ; Monocrotaline/toxicity* ; Rats, Sprague-Dawley ; Hypertension, Pulmonary/chemically induced* ; Endothelial Cells ; Pulmonary Artery ; Endothelium ; Acetylcholine/pharmacology* ; Nitroprusside/pharmacology*

Enbucrilate ; adverse effects ; therapeutic use ; Female ; Humans ; Hypertension, Portal ; diagnosis ; etiology ; Liver Cirrhosis, Biliary ; drug therapy ; Middle Aged ; Pulmonary Embolism ; chemically induced ; diagnosis ; Sepsis ; chemically induced ; etiology

In the present study, we carried out intratracheal administration of bone marrow-derived mononuclear cells (BM-MNCs) to dehydromonocrotaline (DMCT)-induced canine pulmonary artery hypertension (PH) of rat model to examine the security and feasibility, and the aim was to discuss the mechanism. All animals (n=30) were randomly divided into 3 groups (n=10 in each group), i. e. control group, PH group and BM-MNCs group. Six weeks after the transplantation, the hemodynamic data and right ventricle weight ratio were significantly improved for those in BM-MNCs group compared with those in PH group. The lung mRNA levels of vascular endothelial growth factor (VEGF) were higher, while preproendothelin-1 (ppET-1), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were lower compared with those in the PH group (P<0. 05). Immunofluorescence and histochemical results confirmed that 6 weeks after the administration, transplanted BM-MNCs were still alive and could differentiate into pulmonary vascular endothelial cells. These results showed that intratracheal administration of BM-MNCs could obviously reduce or even reverse the DMCT induction of PAH process. The mechanism could be explained as that the function was mainly through the paracrine effect to promote renewable and reduce inflammation.
Animals ; Bone Marrow Cells ; cytology ; Cell Transplantation ; methods ; Dogs ; Familial Primary Pulmonary Hypertension ; Female ; Hypertension, Pulmonary ; chemically induced ; therapy ; Leukocytes, Mononuclear ; transplantation ; Male ; Monocrotaline ; analogs & derivatives ; Rats

OBJECTIVETo observe the pathological changes in the myocardial and pulmonary tissues in miniature pigs with chronic pulmonary hypertension induced by monocrotaline (MCT).

METHODSTwelve male miniature pigs (weigh 15.0-18.0 kg, aged 4.0-4.5 months) were examined for baseline mean pulmonary artery pressure (mPAP), followed by intraperitoneal injection of 10.0 mg/kg MCT in 10 randomly selected pigs. The mean pulmonary artery pressure at 4 and 8 weeks were determined, and the pathological changes in the myocardial and pulmonary tissues were observed.

RESULTSThe baseline mPAP of normal miniature pigs was 15.19∓0.70 mmHg. At 4 and 8 weeks after MCT injection, the sPAP and dPAP were 19.69∓2.47 mmHg and 25.62∓4.88 mmHg, respectively, and the mPAP increased significantly compared with that of the normal control group (P<0.01). Obvious pathological changes such as pulmonary hypertension and right ventricular hypertrophy were found in the pigs 4 weeks after MCT injection, and at 8 weeks, significant pathological changes occurred including right ventricular fibrosis and thickening of the tunica media of the pulmonary artery.

CONCLUSIONMCT can cause pulmonary hypertension in miniature pigs 8 weeks after drug administration, shown as increased pulmonary artery pressure and pulmonary vascular remodeling.

Animals ; Hypertension, Pulmonary ; chemically induced ; pathology ; Lung ; pathology ; Male ; Monocrotaline ; adverse effects ; Myocardium ; pathology ; Swine ; Swine, Miniature

OBJECTIVETo explore the mechanism of pulmonary hypertension and Cor Pulmonale rat models induced by monocrotaline (MCT).

METHODSTwenty Wistar male rats were randomly divided into normal control group and model group (n= 10), which received a single intraperitoneal injection of MCT solution (50 mg/kg , the first day) or dissolvant, respectively. On day 28 after MCT administration, the hemodynamic parameters were assessed; levels of tumour necrosis factor-alpha (TNF-alpha), nitric oxide (NO), endothelin-1 (ET-1), B-type natriuretic peptide(BNP) in pulmonary tissue or blood were measured using radio immunoassay or nitrate reductase method.

RESULTS28 days after MCT injection, compared with control group, right ventricle systolic pressure (RVSP) increased and heart rate(HR), mean arterial pressure (MAP) decreased; Levels of TNF-alpha, NO, ET-1 in pulmonary tissue or blood increased significantly in MCT group.

CONCLUSIONThe potential mechanism of MCI- induced pulmonary hypertension and Cor Pulmonale rat models associates with increasing TNF-alpha, NO, ET-1 levels in vivo, which results from inflammatory injury of lung tissue and blood vessels induced by MCT.

Animals ; Disease Models, Animal ; Endothelin-1 ; metabolism ; Hypertension, Pulmonary ; chemically induced ; metabolism ; physiopathology ; Lung ; metabolism ; Male ; Monocrotaline ; adverse effects ; Nitric Oxide ; metabolism ; Pulmonary Heart Disease ; chemically induced ; metabolism ; physiopathology ; Rats ; Rats, Wistar ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVEPulmonary hypertension is a proliferative vascular disease characterized by pulmonary vascular structural remodeling. Until now, the pathogenesis of pulmonary hypertension is still not fully understood. Although considerable progress has been made, there is, to date, no cure for advanced pulmonary vascular disease. Recently, a number of studies suggest that endogenous vascular elastase (EVE) play a role in the vascular changes associated with pulmonary hypertension. The purpose of the study was to determine whether an elastase inhibitor might reverse advanced pulmonary vascular disease produced in rats by injection of monocrotaline.

METHODSOne hundred and twenty male Sprague-Dawley rats were used in this study. The rats were divided into three groups: control, model and ZD-0892 groups. In the model and ZD-0892 groups, the rats were subjected to a single subcutaneous injection of monocrotaline (60 mg/kg) in the hind flank, while the rats in control group received an equivalent volume of 0.9% saline. From day 21, the rats in the ZD-0892 and model groups received twice-daily gavage tube feedings of either ZD-0892 at a dose of 240 mg/kg per day or its administration vehicle, while the rats in control group were subjected to an equivalent volume of 0.9% saline. On days 21, 28 and 35 post-injection, the elastolytic activity was measured with a fluorescence microplate reader and pulmonary artery pressure was detected via catheterization. Meanwhile, the lungs were evaluated morphologically, using the barium-gelatin perfusion technique.

RESULTSThe injection of monocrotaline led to severe pulmonary hypertension in rats 21 days later and pulmonary artery elastolytic activity increased remarkably. A 1-week treatment with ZD-0892 resulted in declines in elastase activity. This was associated with significant declines in pulmonary artery pressure, decreases in muscularization of peripheral arteries and reductions in medial hypertrophy. After 2 weeks, elastase activity returned to normal level. Pulmonary artery pressure and structure were normalized.

CONCLUSIONIncreased elastase activity is important in the development of vascular changes and progressive pulmonary hypertension. ZD-0892 can suppress the elastase activity and completely reverse the fatal pulmonary hypertension induced by monocrotaline in rats.

Animals ; Hypertension, Pulmonary ; chemically induced ; drug therapy ; Male ; Monocrotaline ; toxicity ; Pancreatic Elastase ; antagonists & inhibitors ; Pulmonary Artery ; drug effects ; pathology ; physiopathology ; Pyrroles ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Sulfonamides ; pharmacology

Intravenous and intratracheal implantation of mesenchymal stem cells (MSCs) may offer ameliorating effects on pulmonary hypertension (PH) induced by monocrotaline (MCT) in rats. The aim of this study was to examine the anti-remodeling effect of intravenous MSCs (VMSCs) and intratracheal MSCs (TMSCs) in rats with PH, and the underlying mechanisms. MSCs were isolated from rat bone marrow and cultured. PH was induced in rats by intraperitoneal injection of MCT. One week after MCT administration, the rats were divided into 3 groups in terms of different treatments: VMSCs group (intravenous injection of MSCs), TMSCs group (intratracheal injection of MSCs), PH group (no treatment given). Those receiving saline instead of MCT served as negative control (control group). Pulmonary arterial structure was pathologically observed, pulmonary arterial dynamics measured, and remodeling-associated cytokines Smad2 and Smad3 detected in the lungs, three weeks after MCT injection. The results showed that PH group versus control group had higher pulmonary arterial pressure (PAP) and wall thickness index (WTI) 21 days after MCT treatment. The expression of phosphorylated (p)-Smad2 and the ratio of p-Smad2/Smad2 were much higher in PH group than in control group. Fluorescence-labeled MSCs were extensively distributed in rats' lungs in VMSCs and TMSCs groups 3 and 14 days after transplantation, but not found in the media of the pulmonary artery. WTI and PAP were significantly lower in both VMSCs and TMSCs groups than in PH group three weeks after MCT injection. The p-Smad2 expression and the ratio of p-Smad2/Smad2 were obviously reduced in VMSCs and TMSCs groups as compared with those in PH group. In conclusion, both intravenous and intratracheal transplantation of MSCs can attenuate PAP and pulmonary artery remodeling in MCT-induced PH rats, which may be associated with the early suppression of Smad2 phosphorylation via paracrine pathways.
Animals ; Atrial Remodeling ; drug effects ; physiology ; Hypertension, Pulmonary ; chemically induced ; physiopathology ; Male ; Mesenchymal Stromal Cells ; pathology ; Monocrotaline ; pharmacology ; Pulmonary Artery ; drug effects ; physiopathology ; Rats ; Rats, Sprague-Dawley