| Objective: To explore the difference of AT1 and AT2 receptors between systemic and pulmonary circulation in children with left-to-right shunt and the relation between the expression of AT1 or AT2 receptors and pulmonary vascular remodeling.Method: Lung and skeletal muscular tissue were obtained from 20 children with left-to-right shunt by biopsy during operation, and lung tissue from 5 childrenabsy autopsy was used as the control group. Above specimens were stained by immunohistochemistry techniques for AT1 and AT2 receptors, a -actin and PCNA. Histomorphometric studies were done to measure the following indexes: the IOD values of pulmonary, skeletal muscular and pleural small vascular walls from staining of AT1 and AT2 receptors, the pulmonary vascular density, muscularization of the nonmuscular vessels, percent wall thickness and proliferation of pulmonary small vascular walls.Result: The IOD values of pulmonary small vascular walls from staining of AT1 and AT2 receptors in children with left-to-right shunt were higher than in control group (P=0. 000), were lower than those of skeletal muscular and pleural small vascular walls inpatients (P < 0.05). And the values from ATI receptor were correlated with the pulmonary vascular density, muscularization of the nonmuscular vessels, percent wall thickness and proliferation of pulmonary small vascular walls(r=-0. 783, 0. 742, 0. 521, 0. 657), while those from AT2 receptor were only correlated with pulmonary vascular density and percent wall thickness(r=-0. 487, 0.516).Conclusion: The expression of ATland AT2 receptors in small vascular walls of systemic circulation was higher than that of pulmonary circulation in children with left-to-right shunt. Angiotensin â…¡ participates in the pulmonary vascular remodeling and formation of pulmonary hypertension in left-to-right shunt. It may provide a sound rationale for the pharmacologicalmanagement to children with left-to-right shunt with ACEI or AT1 receptor antagonist. |
PDF Full Text Request