ObjectiveTo establish a model of fetal hyperglycemia and explore the effects of hyperglycemia on alveolar cell apoptosis,proliferation and the development of lung structure in neonatal rats. MethodsForty SD pregnant rats were randomly divided into a hyperglycemia group (STZ group) and a normal pregnancy group (N group)(n=20 in each group). The rats in STZ group and N group were intraperitoneally injected streptozotocin(STZ,40 mg/kg) or the same bulk of citrate buffer respectively at the 4.5 days after gestation. Blood glucose concentration of the pregnant rats was measured before injection,at the 6.5,11.5,16.5 and 20.5 days after gestation,respectively. The weight,survival rate,lung weight,septal thickness,radical alveolar count,alveolar cell apoptosis and proliferation of neonatal rats were recorded after birth immediately (D0) and at 7 days (D7). ResultsCompared with N group,the blood glucose level increased after intraperitoneal injection of STZ in STZ group (P<0.05). The Survival rate of STZ group was lower than that of N group at D0 and D7 (P=0.00). The neonatal weight,lung weight,septal thickness of STZ group were lower compared with those of N group at D0(P<0.05). However,there was no significant difference between two groups in radical alveolar count. The alveolar apoptosis index of STZ group was higher than that of N group at D0 [(11.8±1.1)% vs. (3.4±0.7)%,P=0.00]. Alveolar cell proliferation significantly increased in STZ group compared with N group at D0 and D7 (P<0.05). ConclusionsThe fetal hyperglycemia model is successfully established by intraperitoneal injection of STZ 40 mg/kg. Fetal hyperglycemia can increase mortality,alveolar cell proliferation and apoptosis,and affect the development of lung structure of neonatal rats.