1.Application of intraoperative arterial pressure-based cardiac output monitoring for patients undergoing coronary artery bypass grafting surgery.
Jia-Kai LU ; Chen ZHU ; He JING ; Yi-Jun WANG ; En-Ming QING
Chinese Medical Journal 2012;125(12):2099-2103
BACKGROUNDFor patients undergoing off-pump coronary artery bypass grafting (OPCABG), it is important to establish a hemodynamic monitoring system to obtain powerful parameters for better intraoperative treatment. This study aimed to observe the clinical feasibility of arterial pressure-based cardiac output (APCO) for cardiac output (CO) monitoring and to evaluate the correlation between APCO and pulmonary artery catheter (PAC) for CO measurement for patients undergoing OPCABG intraoperatively.
METHODSFifty patients of American Society of Anaesthesiologists (ASA) classification II-III, undergoing elective OPCABG at Beijing Anzhen Hospital were randomly enrolled into this study. All patients were assigned to CO monitoring by PAC and APCO simultaneously. Patients with pacemaker, severe valvular heart disease, left ventricular ejection fraction (EF) < 40%, cardiac arrhythmias, peripheral vascular disease, application of intra-aortic balloon pump (IABP) and emergent diversion to cardiac pulmonary bypass were excluded. The radial artery waveform was analyzed to estimate the stroke volume (SV) and heart rate (HR) continuously. CO was calculated as SV ' HR; other derived parameters were cardiac index (CI), stroke volume index (SVI), systemic vascular resistance (SVR), and systemic vascular resistance index (SVRI). PAC was placed via right internal jugular vein and the correct position was confirmed by PAC waveforms. Continuous cardiac output (CCO), CI and other hemodynamic parameters were monitored at following 5 time points: immediate after anesthesia induction (baseline value), anastomosis of left internal mammary artery to left anterior descending artery (LAD), anastomosis of left circumflex (LCX), anastomosis of posterior descending artery (PDA) and immediate after sternal closure.
RESULTSIn the 50 patients, preoperative echocardiography measured left ventricular EF was (52.8 ± 11.5)%, and 35 patients (70%) showed regional wall motion abnormalities. The correlation coefficient of CO monitored by APCO and PAC were 0.70, 0.59, 0.78, 0.74 and 0.85 at each time point. The bias range of CI monitored from both APCO and PAC were (0.39 ± 0.06) L×min(-1)×m(-2), (0.48 ± 0.12) L×min(-1)×m(-2), (0.26 ± 0.06) L×min(-1)×m(-2), (0.27 ± 0.06) L×min(-1)×m(-2), (0.30 ± 0.05) L×min(-1)×m(-2) at each time point. The results of SVR by two hemodynamic monitoring techniques had good correlation during OPCABG. The variation trends of SVR were opposite comparing with the results of CO. SVR collected from PAC obtained the highest value of (1220.0 ± 254.0) dyn×s×cm(-5) at PDA anastomosis, but the highest value obtained from APCO was (1206.0 ± 226.5) dyn×s×cm(-5) in LCX anastomosis.
CONCLUSIONSAPCO is feasible in hemodynamic monitoring for patients undergoing OPCABG. The results of hemodynamic monitoring derived from APCO and PAC are closely correlated. Its characterizations of timely, accurate and continuous display of hemodynamic parameters are also obviously demonstrated in the present study.
Aged ; Arterial Pressure ; physiology ; Cardiac Output ; physiology ; Catheterization, Swan-Ganz ; methods ; Coronary Artery Bypass ; methods ; Female ; Hemodynamics ; Humans ; Male ; Middle Aged ; Monitoring, Intraoperative ; methods
2.Continuous blood purification therapy in 22 children with sepsis.
Guo-ping LU ; Zhu-jin LU ; Ling-en ZHANG ; Jun HE ; Jing HU ; Fang WU
Chinese Journal of Pediatrics 2006;44(8):573-578
OBJECTIVESince continuous blood purification (CBP) has the effects of eliminating inflammatory mediators and improving organs function, CBP had been applied to treat non-renal diseases for nearly 10 years, but few studies have been conducted in children with sepsis and multiorgan dysfunction syndrome (MODS), especially in China. The present study aimed to evaluate the clinical effect of CBP in treatment of children with severe sepsis and MODS.
METHODSTwenty-two children with severe sepsis and MODS admitted to our PICU from Aug. 2003 to Aug. 2005 were treated with continuous veno-venous hemodialysis filtration. Their heart rate, arterial blood pressure, doses of vasoactive agents, spontaneous respiratory rate, PO2/FiO2 and prognosis were investigated.
RESULTSCatheterization and CBP were carried out in all the 22 children. Continuous vein-vein hemodialysis filtration (CVVHDF) and pre-dilution were chosen. The duration of CBP was (64.4 +/- 34.5) h. All the children had tachycardia before CBP and the heart rate fell gradually to 45 +/- 13 bpm 4 h after CBP. Blood pressure (BP) was stable in 7 children without shock during CBP. Ten children with early shock could maintain normal BP during CBP, but the doses of vasoactive agents were tapered 1 to 5 h after beginning of CBP and use of these agents was discontinued at 2 to 8 h. BP was elevated by (25.2 +/- 10.7) mmHg (1 mmHg = 0.133 kPa) in 5 refractorily shocked children 4 h after CBP and returned to normal level 8 h later. The doses of the vasoactive drugs were reduced at 2 to 8 h and ended 4 to 16 h later, which was longer than that of children with early stage shock. The accelerated spontaneous respiratory rate was slowed down by 7 +/- 4 per minute 4 h later, PO2/FiO2 rose from (177.7 +/- 53.1) mmHg before CBP to (341.0 +/- 60.2) mmHg 4 h after CBP in children with respiratory failure and reached the normal value (5.3 +/- 2.1) h later. FiO2 declined to less than 50%. Pediatric critical illness score was 62.2 +/- 7.4 on admission and elevated to (86.6 +/- 9.0) 24 h later, which was a significant elevation as compared to that of children with sepsis who were not treated with CBP seen between Aug. 2001 and July 2003. The survival rate was 72.7% after CBP and the effective rate of the treatment was 90.9%, but was 36% in children who were not treated with CVVHDF.
CONCLUSIONCBP can effectively improve the vital organ's function of children with sepsis and MODS and raise their survival rate. Replacement fluid of modified Ports formula was useful for stability of serum potassium and sodium, but resulted in elevation of serum glucose, calcium, and osmolarity. The application of CBP in children with sepsis can lead to slight drop of blood pressure at the beginning and to bleeding during CBP.
Adolescent ; Blood Pressure ; Child ; Child, Preschool ; Female ; Heart Rate ; Hemofiltration ; methods ; Humans ; Infant ; Infant, Newborn ; Intensive Care Units, Pediatric ; Male ; Multiple Organ Failure ; etiology ; mortality ; physiopathology ; therapy ; Prognosis ; Sepsis ; complications ; mortality ; physiopathology ; therapy ; Severity of Illness Index ; Survival Rate ; Treatment Outcome
3.The effect of angiotensin II type 1 receptor blocker valsartan in preventing hepatic fibrosis induced by dimethylnitrosamine in rats.
Feng-jun SHEN ; Yue-ke ZHU ; Ji-dong JIA ; Hong MA ; Bao-en WANG
Chinese Journal of Hepatology 2004;12(10):605-608
OBJECTIVETo observe the effects of angiotensin II type 1 receptor blocker valsartan in preventing hepatic fibrosis induced by dimethylnitrosamine in rats.
METHODSExcept rats in the control group, all were given intraperitoneal injections of 1% dimethylnitrosamine (DMN 1 ml/kg, two or three consecutive days/a week for 6 weeks). From the first day of the intraperitoneal injection, rats in treatment groups were given valsartan for 8 weeks by gastric gavage. Liver tissue and blood samples of all rats were examined at 56 days (8 weeks). AngII levels were determined by radioimmunoassay. Hepatic mRNA levels of Collagen type I (Col I) and tissue inhibitor of metalloproteinase1 (TIMP1) were evaluated by reverse-transcription polymerase chain reaction (RT-PCR).
RESULTSValsartan significantly attenuated the degree of liver fibrosis and decreased the hepatic AngII content compared with DMN treated rats (P<0.01). mRNA levels of Col I and TIMP1 were upregulated in DMN treated rats compared with normal rats. Valsartan downregulated the elevation of Col I and TIMP1 mRNA levels (P<0.01).
CONCLUSIONHepatic AngII content of the model group was increased, the local tissue RAS was activated in DMN induced liver fibrosis. Valsartan can retard the progression of hepatic fibrosis and may provide an effective new strategy for anti-liver fibrosis therapy.
Angiotensin II Type 1 Receptor Blockers ; pharmacology ; therapeutic use ; Animals ; Dimethylnitrosamine ; Female ; Liver Cirrhosis, Experimental ; chemically induced ; prevention & control ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Tetrazoles ; pharmacology ; therapeutic use ; Valine ; analogs & derivatives ; pharmacology ; therapeutic use ; Valsartan
4.Effect of continuous veno-venous hemodiafiltration on hemodynamics of piglets with endotoxin-induced acute lung injury.
Jing-yu GONG ; Guo-ping LU ; Jun HE ; Zhu-jin LU ; Ling-en ZHANG
Chinese Journal of Pediatrics 2008;46(5):340-343
OBJECTIVETo investigate the effect of continuous veno-venous hemodiafiltration (CVVHDF) on endotoxin-induced acute lung injury (ALI) of piglets.
METHODSEighteen piglets were randomly divided into three groups: control group (n = 6); heparin group (n = 6) and CVVHDF treatment group (n = 6). All the animals were anesthetized by muscle injection of ketamine (30 mg/kg), then placed in supine position, received continuous intravenous infusion of ketamine with the rate of 10 mg/(kgxh). After placing a 4.5 cm (inner diameter) tracheal tube via tracheostoma, controlled mechanical ventilation was established using the assisted-controlled ventilation option of the NEWPORT 200. Respiratory rate at 30 breath/min; PIP at 10 cm H2O (1 cm H2O = 0.098 kPa); PEEP at 2 cm H2O and fraction of inspired oxygen at 0.3. A vein catheter was placed into right vena jugularis interna to administer a Ringer's solution. Initially, at a rate of 10 ml/kg, followed by a rate of 15 ml/kg when the mean arterial blood pressure was below 70 mm Hg (1 mm Hg = 0.133 kPa), the rate of 20 ml/kg was used when the mean arterial blood pressure was below 60 mm Hg. An 8Fr double-lumen catheter was inserted into left femoral vein and served as the pathway for CVVHDF. A Pulsiocath Pcco catheter was positioned into left femoral artery to monitor the circulatory parameters. All catheters were flushed with heparinized saline to prevent clotting. Then all the animals were given intravenous infusion of 150 microg/kg endotoxin within 30 minutes to induce ALI. When the oxygenation index < 300 and pulmonary compliance < 30% of the baseline, the animals of heparin group received heparin infusion to maintain blood active coagulation time (ACT) 180 - 250 s, the animals of treatment group received CVVHDF with the blood flow of 50 ml/min, replacement rate of 300 ml/h, dialysis rate of 600 ml/h and the ultrafiltrate rate of 350 ml/h for six hours, heparin infusion to keep blood ACT 180 - 250 s. The circulatory parameters: heart rate (HR), mean arterial blood pressure (MABP), central venous pressure (CVP), pulse contour cardiac output index (PCCI); systemic venous resistance index (SVRI), cardiac function index (CFI), external venous lung water index (EVLWI), left ventricular contractile index (dPmx); respiratory parameters: respiratory rate (RR), pulmonary compliance (Cdyn) were monitored; arterial blood gas analysis was performed and oxygenation index (PaO2/FiO2) was calculated. All the parameters were recorded at baseline (B), onset of ALI (A 0 h), two hours (A 2 h), four hours (A 4 h), six hours (A 6 h) after ALI.
RESULTSNo significant difference in circulatory parameters, respiratory parameters and blood gas analysis were found at B and A 0 h among the three groups. When the ALI occurred, PaO2/FiO2, Cdyn, MABP and PCCI of the three groups decreased; HR, RR, EVLWI, SVRI increased. After four hours of ALI, the RR, EVLWI, SVRI, CFI and dPmx of treatment group were improved, the differences were significant compared with the other two groups (P < 0.05). After six hours of ALI, the HR, PCCI, MABP, PaO2/FiO2 and Cdyn of treatment group were significantly improved, compared with control group and heparin group (P < 0.05). There were no significant differences in any of the parameters between control group and heparin group. The difference in CVP among three groups was not significant.
CONCLUSIONCVVHDF has a good effect on hemodynamics of the endotoxin-induced ALI of the piglets.
Acute Lung Injury ; etiology ; physiopathology ; therapy ; Animals ; Endotoxins ; adverse effects ; Hemodiafiltration ; Hemodynamics ; Swine
5.Awareness of diabetes and its influencing factors among the elderly population in Shanghai rural community
Chao-Yu ZHU ; Yue-Qin MAO ; Chun-Jun MA ; Zhi-Jun ZHU ; Mu-Song LIU ; En-Fang FAN ; Li WEI
Chinese Journal of Clinical Medicine 2017;24(4):611-614
Objective:To investigate the awareness of diabetes and to explore the influencing factors of it among the elderly population in Shanghai rural community.Methods:A cross-sectional study method was used in the research.Epidemiological investigation was undertaken in residents of 40-75 years old in Yunsong Commuinity of Pudong New Area in March to April,2014.Among the population,diabetic patients were selected to conducted questionnaire survey,physical examination,and laboratory testing.Objective:A total of 256 diabetic patients completed questionnaires.The awareness rate of diabetes was 50.78%(130/256).The awareness rate of diabetes indicated that the statistical significance was found in patients with different educational background,blood lipid level,fasting blood-glucose level,HbA1c and exercise habits(P<0.05).The multi-factor logistic stepwise regression analysis showed that the educational level,glycosylated hemoglobin level and exercise habits were the main independent influencing factors for the awareness rate of diabetes.Conclusions:The level of awareness rate of diabetes in Shanghai Yunsong community is in the moderate level.Education should be strengthened to increase the rate of diabetes awareness for patients with low educational background,worse glucose control and no exercise habit.
6.The change of telomere protein in BEAS-2B malignant transformation cell induced by coal tar pitch smoke extracts.
Wei WANG ; Zhi-Tao LI ; Han-Song ZHU ; Yong ZHAO ; Li-Xia WANG ; Zhen YAN ; I Shi-En L ; Dong XU ; Wei-Dong WU ; Yong-Jun WU ; Yi-Ming WU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2011;29(9):678-681
OBJECTIVEBy testing the changes of telomere binding protein in malignant transformation BEAS-2B cells induced by coal tar pitch smoke extracts, to study the role of protection of telomeres 1 (POT1), telomeric repeat binding factor 1 (TRF1) and TRF2 in tumorgenesis that contact with coal tar pitch.
METHODSThe BEAS-2B cells were induced by coal tar pitch smoke extracts to form malignant transformation cell model in vitro. The gene expression levels of mRNA were assessed by real-time quantitative RT-PCR, the protein expression variations were determined by cell culture overslip of immunohistochemical methods.
RESULTSIn malignant transformation cells, the mRNA expression level (POT1: 0.63 ± 0.04, TRF1: 0.36 ± 0.01) and the protein expression level (POT1: 0.36 ± 0.05, TRF1: 0.09 ± 0.03) of POT1 and TRF1 was statistically significant decreased compared to that of BEAS-2B group (mRNA: POT1: 1.00 ± 0.04, TRF1: 1.01 ± 0.16; protein: POT1: 0.55 ± 0.07, TRF1: 0.27 ± 0.07) and DMSO group (mRNA: POT1: 0.89 ± 0.12, TRF1: 0.90 ± 0.08; protein: POT1: 0.55 ± 0.10, TRF1: 0.26 ± 0.04) (P < 0.05); mRNA expression level (1.45 ± 0.07) and the protein expression level (0.88 ± 0.06) of TRF2 was increased compared to that of BEAS-2B group (mRNA: 1.00 ± 0.07, protein: 0.48 ± 0.06) and DMSO group (mRNA: 1.00 ± 0.06, protein: 0.50 ± 0.06) (P < 0.05).
CONCLUSIONThe change of gene and protein expression level in POT1, TRF1, and TRF2 involved in the process that evolved into malignant transformation in bronchial epithelial cells BEAS-2B induced by coal tar pitch smoke extracts.
Cell Line ; Cell Transformation, Neoplastic ; metabolism ; Coal Tar ; toxicity ; Epithelial Cells ; cytology ; metabolism ; pathology ; Humans ; Repetitive Sequences, Nucleic Acid ; Telomere-Binding Proteins ; genetics ; metabolism
7.Pulmonary pathology in fatal human influenza A (H1N1) infection.
Xue-jing DUAN ; Yong LI ; En-cong GONG ; Jue WANG ; Fu-dong LÜ ; He-qiu ZHANG ; Lin SUN ; Zhu-jun YUE ; Chen-chao SONG ; Shi-Jie ZHANG ; Ning LI ; Jie DAI
Chinese Journal of Pathology 2011;40(12):825-829
OBJECTIVETo study the pulmonary pathology in patients died of fatal human influenza A(H1N1) infection.
METHODSEight cases of fatal human influenza A (H1N1) infection, including 2 autopsy cases and 6 paramortem needle puncture biopsies, were enrolled into the study. Histologic examination, immunohistochemitry, flow cytometry and Western blotting were carried out.
RESULTSThe major pathologic changes included necrotizing bronchiolitis with surrounding inflammation, diffuse alveolar damage and pulmonary hemorrhage. Influenza viral antigen expression was detected in the lung tissue by Western blotting. Immunohistochemical study demonstrated the presence of nuclear protein and hemagglutinin virus antigens in parts of trachea, bronchial epithelium and glands, alveolar epithelium, macrophages and endothelium. Flow cytometry showed that the apoptotic rate of type II pneumocytes (32.15%, 78.15%) was significantly higher than that of the controls (1.93%, 3.77%).
CONCLUSIONNecrotizing bronchiolitis, diffuse alveolar damage and pulmonary hemorrhage followed by pulmonary fibrosis in late stage are the major pathologic changes in fatal human influenza A (H1N1) infection.
Adolescent ; Adult ; Aged ; Alveolar Epithelial Cells ; pathology ; Antigens, Viral ; metabolism ; Apoptosis ; Autopsy ; Biopsy, Needle ; Bronchiolitis, Viral ; pathology ; Child ; Child, Preschool ; Female ; Hemagglutinin Glycoproteins, Influenza Virus ; metabolism ; Humans ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza, Human ; metabolism ; mortality ; pathology ; virology ; Lung ; immunology ; metabolism ; pathology ; Male ; Middle Aged ; Nuclear Proteins ; metabolism ; Pulmonary Alveoli ; pathology ; Pulmonary Fibrosis ; pathology ; Young Adult
8.Dynamic evolution of MMP-2 gene expression and its enzymatic activities in experimental liver fibrosis.
Yue-ke ZHU ; Bao-en WANG ; Feng-jun SHEN ; Ji-dong JIA ; Hong MA
Chinese Journal of Hepatology 2005;13(7):509-512
OBJECTIVESTo explore the dynamic changes and interactions between MMP-2 and TIMP-2 during experimental liver fibrosis.
METHODSWistar rats were randomly allocated into a normal group and a model group. To induce liver fibrosis, rats were injected intraperitoneally with dimethylnitrosamine (DMN) three consecutive times in the first week, then two consecutive times per week, totally for 6 weeks. In the normal control group, rats were injected with saline by the same method as the model group. Animals were sacrificed 1, 4, 10, 17, 28, 42, 56 days after starting DMN injections. Conventional histological examinations of the livers were performed with hematoxylin and eosin and Masson staining. The fibrosis was classified into 0 to 4 stages. Hydroxyproline content was determined after liver tissues were hydrolyzed in HCl at 160 degree C for 2 hrs and then measured with spectrometry at 560 nm wavelength. mRNA levels of MMP-2 and TIMP-2 were determined by semi-quantitive RT-PCR. Gelatinase activity of MMP-2 was examined by zymography using gelatin substrate.
RESULTSIn the model group the hepatic MMP-2 mRNA expression started to increase 10 days after DMN administration and remained at a much higher level than in the normal group throughout the study period, while TIMP-2 mRNA expression started to be lower than in the normal group 17 days after DMN administration and reached the lowest level on the 28th day. Then it rapidly rebounded and remained higher than that in the normal group from the 42nd day to the end of the study period. TIMP-2/MMP-2 began to be lower by several days than that of the normal group after DMN administration through the remaining study period. Zymography showed that the enzymatic activities of both latent MMP-2 and active MMP-2 were increased during the process of liver fibrosis.
CONCLUSIONIn liver fibrosis, MMP-2 expression increases, while TIMP-2 expression relatively decreases. The enzymatic activities of MMP-2 increase as the liver fibrosis develops.
Animals ; Female ; Liver Cirrhosis, Experimental ; enzymology ; metabolism ; Male ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-2 ; biosynthesis ; genetics ; metabolism
9.A novel mouse model of human breast cancer stem-like cells with high CD44+CD24-/lower phenotype metastasis to human bone.
Li-jun LING ; Shui WANG ; Xiao-an LIU ; En-chao SHEN ; Qiang DING ; Chao LU ; Jian XU ; Qin-hong CAO ; Hai-qing ZHU ; Feng WANG
Chinese Medical Journal 2008;121(20):1980-1986
BACKGROUNDA satisfactory animal model of breast cancer metastasizing to bone is unavailable. In this study, we used human breast cancer stem-like cells and human bone to build a novel "human-source" model of human breast cancer skeletal metastasis.
METHODSHuman breast cancer stem-like cells, the CD44+/CD24-/lower subpopulation, was separated and cultured. Before injection with the stem-like cells, mice were implanted with human bone in the right or left dorsal flanks. Animals in Groups A, B, and C were injected with 1 x 10(5), 1 x 10(6) human breast cancer stem-like cells, and 1 x 10(6) parental MDA-MB-231 cells, respectively. A positive control group (D) without implantation of human bone was also injected with 1 x 10(6) MDA-MB-231 cells. Immunohistochemistry was performed for determination of CD34, CD105, smooth muscle antibody, CD44, CD24, cytokine, CXC chemokine receptor-4 (CXCR4), and osteopontin (OPN). mRNA levels of CD44, CD24, CXCR4, and OPN in bone metastasis tissues were analyzed by real-time quantitative polymerase chain reaction (PCR).
RESULTSOur results demonstrated that cells in implanted human bones of group B, which received 1 x 10(6) cancer stem-like cells, stained strongly positive for CD44, CXCR4, and OPN, whereas those of other groups showed no or minimum staining. Moreover, group B had the highest incidence of human bone metastasis (77.8%, P = 0.0230) and no accompaniment of other tissue metastasis. The real-time PCR showed an increase of CD44, CXCR4, and OPN mRNA in metastatic bone tissues in group B compared with those of groups C and D, however the expression of CD24 mRNA in group B were the lowest.
CONCLUSIONSIn the novel "human source" model of breast cancer, breast cancer stem-like cells demonstrated a higher human bone-seeking ability. Its mechanism might be related to the higher expressions of CD44, CXCR4, and OPN, and the lower expression of CD24 in breast cancer stem-like cells.
Animals ; Bone Neoplasms ; secondary ; Breast Neoplasms ; pathology ; CD24 Antigen ; analysis ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Hepatocyte Growth Factor ; pharmacology ; Humans ; Hyaluronan Receptors ; analysis ; Immunohistochemistry ; Mice ; Neoplastic Stem Cells ; pathology ; Osteopontin ; analysis ; Phenotype ; Receptors, CXCR4 ; analysis
10.Dynamic evolution of MMP-13, TIMP-1, type I and III collagen and their interaction in experimental liver fibrosis.
Yue-ke ZHU ; Bo-en WANG ; Feng-jun SHEN ; Ai-min WANG ; Ji-dong JIA ; Hong MA
Chinese Journal of Hepatology 2004;12(10):612-615
OBJECTIVETo obtain a detailed pattern of the dynamic evolution and interactions among MMP-13, TIMP-1, type I and III collagen during experimental liver fibrosis.
METHODSWistar rats were randomly allocated into a normal group, and a model group. To induce liver fibrosis, rats were intraperitoneally injected with dimethylnitrosamine (DMN) three consecutive times in the first week, then two consecutive times per week, totally for 6 weeks. In the normal control group, rats were treated with saline by the same means. Animals were sacrificed 1, 4, 10, 17, 28, 42, 56 days after starting DMN injections. Conventional histological examinations were performed after hematoxylin and eosin, and Masson stain. Fibrosis stages were classified into 0 to 4. Hydroxyproline contents were determined after liver tissues were hydrolyzed in HCl at 160 degrees C for 2 h and then measured with spectrometry at 560 nm wavelength. mRNA levels of MMP-13, TIMP-1, type I and III collagen were determined by semi-quantitive RT-PCR.
RESULTSIn the model group, hepatic type I pro-collagen mRNA expression started to increase on the 10th day after DMN administration (t = 2.85, P < 0.05), type III started to increase on the 28th day (t = 4.16, P< 0.01), and TIMP-1 mRNA expression started to increase on the 4th day (t = 2.60, P < 0.05). They all remained much higher than in the normal group throughout the remaining study period. Hepatic MMP-13 mRNA expression started to increase on the 17th day after DMN administration and remained at a higher level than in the normal group until he 28th day (t = 4.08, P < 0.01), then gradually returned to normal level at the end of the study period.
CONCLUSIONAlthough hepatic MMP-13 expression transiently increased during liver fibrosis, enhanced expression of TIMP-1 from the early periods of liver fibrosis inhibited the collagen degrading ability of MMP-13, therefore, over-expressed collagen accumulated in the liver. Thus, it is hypothesized that TIMPs play a pivotal role in liver fibrosis.
Animals ; Collagen Type I ; biosynthesis ; genetics ; Collagen Type III ; biosynthesis ; genetics ; Collagenases ; biosynthesis ; genetics ; Dimethylnitrosamine ; Female ; Liver Cirrhosis, Experimental ; chemically induced ; metabolism ; Male ; Matrix Metalloproteinase 13 ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-1 ; biosynthesis ; genetics