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Heparin as an anticoagulant in clinical applications for more than 50 years. In addition to the anticoagulant effect of heparin, there are many other biological effects, such as adjusting the enzymes of metabolic control of cells with a variety of proteins in the extracellular matrix binding, binding to cell growth factor, etc., and recent studies found that heparin can inhibit vascular smooth muscle cells (smooth proliferation of muscle cell.SMC). Cell proliferation by a variety of cell cycle regulatory factor adjustment, P27 is a cyclin-dependent kinase inhibitor factor (cyclin-dependent kinase inhibitor, CKI) through inhibition of cyclin-dependent kinase - cyclin complexes (Cdk- Cyclin) activity to the regulation of cell cycle process, is an important regulatory molecules of G 1 / S phase restriction point. The important pathological hypoxic pulmonary hypertension (hypoxia-induced pulmonary hypertension, HPH) is characterized by hyperplasia and hypertrophy of pulmonary artery smooth muscle cells (pulmonary artery smooth muscle cell, PASMC). Thompson, Khoury observed in vitro and in vivo study to heparin can inhibit PASMC proliferation, thereby reducing the extent of HPH, but its mechanism is still not clear. We assume that the negative regulator of cell cycle P27 involved in this process, the experiment will conduct a preliminary study in this regard. Materials and methods, experimental animals 24 rats were randomly divided into three groups, the control group (A, n = 8), hypoxia group (B, n = 8), hypoxia and heparin intervention group (C, n = 8). B, C groups in the the hypoxic compartment, continuous hypoxia 8h [oxygen concentration (10 ± 0.5)%] daily for two weeks in a row, C group were intraperitoneally hypoxia of the day before the start and after the end of heparin (300u/kg), A, B two groups at the corresponding time intraperitoneal injection of saline 0.4 ml of the same group of animal husbandry and diet conditions. Right heart catheterization, measured the RVSP instead pulmonary pressure, right ventricular systolic pressure measurement (right ventricular systolic pressure.RVSP) hypoxic two weeks. Drawn with the preparation of the lung tissue was measured RVSP chest was opened, whichever side of the lobe for immunohistochemistry assay, take the other side of the lobe, used for RT-PCR analysis. Immunohistochemical results grayscale scanning computer analysis, RT-PCR results with the purpose fragments with internal reference absorbance ratio of the bands that. Statistical data expressed as mean ± standard deviation, were statistically analyzed using SPSS software, P <0.05 was considered statistically significant. Results, right ventricular systolic pressure (RVSP) hypoxic two weeks after right heart catheterization Determination RVSP. Use of the group design data sample mean comparison q test for comparison between groups group B than in group A (P <0.01) in group B than group C (P <0.01), group C than in group A (p < 0.01). The expression of P27 immunohistochemistry results grayscale value comparison: group B than in group A (p <0.01) in group A than in group C (p <0.01) group B than in group C (p <0.01). Corresponding to the number of positive cells: C group than in group A, group A than in group B. Third, the P27 RT-PCR results in each group P27 strip GAPDH bar with the absorbance ratio p27mRNA the test results were different (p <0.01), to hypoxia and content of heparin in the intervention group is the highest, followed by the control group, simple hypoxia group content of at least. Conclusion p27 heparin inhibit an important factor in the mechanism of hypoxic pulmonary hypertension and hypoxia can inhibit the generation of p27.
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