AIM: To investigate the changes of vascular endothelial growth factor (VEGF) in the pulmonary circulation of rats with different hypoxia and hypercapnia duration. METHODS: Forty SD rats were randomly divided into normol control group (N), exposed to hypoxia hypercapnia for 2 weeks group (T), for 4 weeks group (F), for 8 weeks group (E). The levels of VEGF were measured and the ultrastructure of pulmonary arterioles was observed by electron microscopy. RESULTS: Mean pulmonary arterial pressure (mPAP), weight ratio of RV to LV+S, the levels of VEGF in serum and lung tissue, the expression of VEGF and VEGF mRNA in group T, F, E were significantly higher than that in group N. With the prolong duration, base of endothelial cell was narrowed, proliferation of smooth muscle cells and collagenous fibers of pulmonary arterioles in rats were increased gradually. CONCLUSIONS: Hypoxia and hypercapnia increase the expression of VEGF mRNA and synthesis of VEGF. VEGF may play an important role in the pathogenesis of hypoxia pulmonary hypertension and reconstruction of pulmonary artery.

AIM:To investigate rat Urotensin-II(ra t U-II)-induced vasoconstriction of rat main pulmonary arteries and the role of mitogen-activated protein kinase(MAPK). METHODS: The main pulmon ary artery was dissected from the male Sprague -Dawley rats and artery ring width was 3-4 mm. Concentration-response curves wer e gene rated to rat U-II(0 03 nmol/L-30 nmol/L).Inhibitor of MAPK,PD 98059(0 1 ?mol/ L -10 ?mol/L) were added into the medium after rat U-II(30 nmol/L)induced vasoc onstriction had reached plateau to construct the relaxant concentration-respons e curves and their EC 50 and E max . RESULTS: Rat U-II was a potent vasoconstrictor of isolated rat main pulmonary arteries [EC 50 =7 95?0 4 0, E max =(14 28?6 34)% of the response to 60 mmol/L KCl]; PD 98059 caused c oncentration-dependent relaxations of rat U-II precontracted arteries [EC 50 =5 91?0 45, E max =(81 39?13 65)%]. CONCLUSION: Rat U- II was a potent vasoconstrictor of rat main pulmonary arteries and this response was med iated through MAPK.

Objective To investigate clinical characteristics and renal uric acid excretion in early-onset gout patients.Methods Consecutive inpatients with primary gout were recruited between 2013 and 2017.The patients with gout onset younger than 30 were defined as early-onset group while the others were enrolled as control group.Clinical characteristics and uric acid (UA) indicators were compared between two groups.Results Among 202 recruited patients,the early-onset group included 36 patients (17.8％).Compared with control group,the early-onset group presented more patients with obesity [13 patients (36.1％) vs.22 patients (13.3％),P＜0.05],significantly higher serum UA level [(634± 124)μmol/L vs.(527± 169).μmol/L] and glomerular load of UA[(7.2±2.8)mg· min-1 · 1.73m-2 vs.(4.4±2.2)mg· min-1 · 1.73m-2] and estimated glomerular filtration rate (GFR) [(83±21)ml· min-1 · 1.73m-2 vs.(67±21)ml· min-1 · 1.73m-2] (all P＜ 0.05),lower fractional excretion of UA [4.4％ (3.4％,6.1％) vs.7.2％ (5.2％,9.6％),P＜0.05],whereas 24h urinary UA excretion was comparable [(2 788±882)l,μmol/1.73m2 vs.(2 645±1 140)μmol/1.73m2,P=0.274].Subgroup analysis of patients without chronic kidney disease showed significantly lower fractional excretion of UA in the early-onset group [4.5％(3.3％,6.1％) vs.6.7％ (5.1％,8.7％),P＜0.05].Logistic regression analysis showed that obesity (OR=3.25) and fractional excretion of UA less than 7％ (OR=9.01,all P＜0.05) were risk factors of gout early onset.Conclusion The gout patients with early-onset younger than 30 present high serum and glomerular load of uric acid which might be due to obesity and relative under-excretion of renal uric acid.