RESUMO
Objective To assess the effects of PI3K/mTOR dual inhibitor NVP-BEZ235 on the distribution and degranulation of perivascularmast cells in the lung of hypobaric hypoxia rats.Methods SD male rats in the hypoxia group were raised in the specific hypoxic incubator (50.5 kPa).The intervene group received NVP-BEZ235 training (35 mg/kg) intervention once every two days.The control group was fed in the conditions comparable to the other groups at local pressure and normoxia environment.After 21 days, all rats were sacrificed with injection of 5％ pentobarbital sodium.Lung tissues were fixed and embedded in paraffin for further hematoxylin-eosin staining and toluidine blue staining.Results Compared with the control group, the number of pulmonary perivascular mast cells in the hypoxia group increased significantly.Hypoxia group had more mast cell accumulation and larger degranulation ratio around different diameters of pulmonary vessels (less than 50 μm, 50-100 μm, larger than 100 μm) than the control group (P< 0.05).The mast cell numbers decreased in NVP-BEZ235 intervention group compared with hypoxia group (P<0.05).The degranulation ratio of pulmonary vascular mast cells around 50-100 μm in the intervention group was smaller than the hypoxia group (P=0.000 3).Conclusion NVP-BEZ235 inhibits the aggregation of pulmonary perivascular mast cells and degranulation ratio of median diameter pulmonary perivascular mast cells in hypobaric hypoxia rats.