Objective To evaluate the effect of propofol (PPF) on stress response and lung injury in rats with traumatic brain injury (TBI).Methods A total of 36 SD rats were randomly (random number)divided into sham group,intralipid group,TBI group,PPF1 h group,PPF 2 h group,PPF 6 h group (n =6 in each group).Fluid percussion brain injury models were used.By intraperitoneal injection,intralipid was administered in intralipid group after sham operations,while propofol 100 mg · kg-1 was given to rats in PPF1 h group,PPF 2 h group and PPF 6 h group 1,2,6 hours following injury,respectively.Nerve motor function were scored at different intervals,serum concentrations of adrenocorticotropic hormone (ACTH),cortisol (COR) and norepinephrine (NE) were measured 12 h after injury.Seventy-two hours later,all rats were sacrificed and brains were harvested for TTC staining,and lungs taken were stained with HE staining for observation under light microscope and electron microscopy.Results Compared with sham and intralipid group,nerve motor function scores were significantly decreased,and serum concentrations of ACTH,COR and NE were increased significantly in rats after injury.Compared with TBI group,the above biomarkers were improved significantly after propofol injection.There were no significant differences in above biomarkersbetweenPPF 1 hand PPF 2 h group (t=-0.816,t=-0.208,t=0.582,P＞0.05).The differences in COR and NE concentrations between PPF 2 h and PPF 6 h group were statistically significant (t =3.018,P =0.013;t =3.662,P =0.004).Light microscopy demonstrated abundant inflammatory cell infiltration and massive thickening of the alveolar walls,Electron microscopy showed Type Ⅱ lung epithelial cell swelling,vacuolar degeneration,osmiophilic lamellar corpuscle emptying in cytoplasm,microvilli protrusions decreases in some cytoplasm in TBI group,and pathological damage was improved significantly in PPF 2 h group.Conclusions Propofol may inhibit stress and protect the lung tissue from damage in TBI rats.

Objective: To establish an animal model of hypoxia-induced bronchopulmonary dysplasia asso-ciated with pulmonary hypertension (BPD-PH). Methods: C57BL/6 male and female specific pathogen free mice mated and female mice with their offspring mice were randomly divided into normoxic group and hypoxia group by way of numerical method.Normoxic group was placed in the indoor environment directly.Hypoxia group was placed in 120 mL/L oxygen concentration environment within 12 hours after birth.Body weight gain and mortality of the neonatal mice were recorded.The mice lungs and hearts were harvested on day 14 for immunofluorescence staining and HE staining, and Western blot was used to observe the morphological changes and vascular endothelial growth factor (VEGF) protein level. Results: The mortality rates of normoxic group and hypoxic group were 11.8% and 47.3%, respectively.Compared with the normoxic group, body weight of hypoxia group increased slowly, as the final body weight of 2 groups were (12.40±2.33) g and (5.50±0.32) g, respectively, and the difference was significant (χ²=13.38, t=20.50, all P<0.01). Hypoxia group showed higher right ventricular hypertrophy index [(96.00±0.15)% vs.(40.40±4.00)%, t=41.67, P<0.01], fusion of alveolar, diminished microvasculature, thickening alveolar septal, decreased alveolar radiation coefficient (RAC)(19.73±2.33 vs.10.90±1.85) and increased mean linear intercept(MLI) (33.2±4.33 vs.58.70±7.27) with statistical significance, respectively (t=16.27, 9.53, all P<0.01). In the lung HE staining, pulmonary arterial thickening, pulmonary smooth muscle cell proliferation and intimal roughness in immunofluorescence, significantly decreased expression of VEGF protein level by Western blot were observed in hypoxic group (0.41±0.04 vs.1.19±0.08, t=15.10, P<0.01). Conclusions Hypoxia-induced mouse BPD-PH model was consistent with the pathophysiological process of pulmonary vascular remodeling of pulmonary hypertension, which increase pulmonary vascular resistance eventually leading to right ventricular hypertrophy.