[The construction and application of a novel apparatus for detecting oxygen consumption of mice under normobaric hypoxia].

OBJECTIVE: To establish a method for real-time recording the oxygen consumption of mice under normobaric hypoxia. METHODS: The experimental apparatus was made up of animal container, filling water control system, electronic balance, hose, a computer with weight recording software, etc. The working principle was that the oxygen consumed by animal was replaced by water filling which was controlled by the pneumatic and hydraulic actuator. The water was weighted by an electronic balance and the weight signal was recorded into excel file at the same time. The accuracy and precision of the apparatus were detected by a 10 ml syringe. The oxygen consumption characteristics of 6 acute repetitive hypoxia mice and 6 normal mice were observed. RESULTS: The P value for the paired t test was 1 and the CV value was 4%. The survival time and total oxygen consumption of acute repetitive hypoxia mice were both significantly increased compared to normal mice (P < 0.05), which were (58.8 +/- 6.8) min and (46.0 +/- 8.7) min respectively for the survival time and (85.1 +/- 8.5) ml and (73.6 +/- 5.4) ml respectively for total oxygen consumption. CONCLUSION: The hypoxia tolerance of the acute repetitive hypoxia mice can significantly improved by taking more oxygen in the animal cabin. The accuracy and precision of the apparatus are high and it can be used for the determination of oxygen consumption in hypoxia research.

[Choline promotes angiogenesis in chick embryo chorioallantoic membrane].

OBJECTIVE: To investigate choline promoting angiogenesis on chick embryo chorioallantoic membrane (CAM). METHODS: CAM model was prepared, the choline chloride, human vascular endothelial growth factor (hVEGF) and normal saline were added respectively onto the carrier on the CAM, the state of angiogenesis was observed and the number of new blood vessels was counted. RESULTS: Choline chloride was tested at the concentrations of 0.5 nmol/L - 1 mmol/L in this experiment, when its concentrations were increased to 0.01 micromol/L - 1 000 micromol/L, it could stimulate angiogenesis, the minimum effective concentration was tested as 0.01 micromol/L, and its effect for promoting the angiogenesis was equivalent to that of hVEGF, the potent stimulator for angiogenesis. CONCLUSION: The result shows that choline can promote angiogenesis in the chick embryo chorioallantoic membrane.