[Effect of different hypoxic duration on changes of pulmonary circulation]

In order to assess the relationship between the hypoxic duration and pulmonary hypertension, we investigated the pulmonary hemodynamics and right ventricular hypertrophy and pulmonary vascular structure changes in rats with hypoxic exposure for 1 day to 3 weeks. After hypoxic treatment, the pulmonary artery pressure of rats increased in 3 days, and it was up to peak at 2 weeks later. The weight of right ventricle of rats significantly increased after 1 week. The endothelium of pulmonary vascular of rats became swollen in 3 days, and then increased in extracellular matrix deposition. Vessel wall thickening was found in 1 week hypoxic rats, and it was very significant in 3 week hypoxic rats. The results suggest that the duration of hypoxic treatment is related to the change of pulmonary circulation in 3 weeks in rats.