Objective：To investigate the characteristics of fat metabolism in rat skeletal muscle after hypobaric hypoxia acclimation. Methods： Sprague-Dawley rats were divided into 3 groups randomly： control group （H0）, hyp...Objective：To investigate the characteristics of fat metabolism in rat skeletal muscle after hypobaric hypoxia acclimation. Methods： Sprague-Dawley rats were divided into 3 groups randomly： control group （H0）, hypoxic 5-day group （HS）, and hypoxic 15-day group （H15）. Animals of H5 and 15 groups were exposed to hypobaric hypoxia chamber simulating 5 000 m high altitude for 5 d or 15 d respectively, 23 h per day. H0 group stayed outside of chamber The level of fatty acid oxidation and uptake, and glucose oxidation were examined, and the level of non-esterified fatty acids （NEFA）, ATP and phosphocreatine （PCr） were also assayed in rat skeletal muscles. Results： The contents of ATP and PCr in H5 group were lower than those in H0 and H15 groups （P〈0.05）, while there was no significant difference between H0 and H15. Compared with H0, the blood NEFA level in all hypoxia groups was increased significantly （P〈0.05）. The muscle NEFA level in H15 group was greatly higher than that in H0 and H5 groups. The rates of fatty acid oxidation and uptake in H15 group were significantly higher than those in H0 and H5 groups （P〈0.05）, and the rate of glucose oxidation in all hypoxia groups was significantly decreased than that in H0 group （P〈0.05）. Conclusion： It is concluded that the enhanced fat oxidation may be one of the mechanisms in the maintenance of energy homeostasis after hypobaric hypoxic acclimation.展开更多
The fructose modified chitosan microcarries (CMs) were prepared by the reaction of glutaraldehyde with fructose-modified chitosan. Various factors that influence the preparation were studied and the reaction condition...The fructose modified chitosan microcarries (CMs) were prepared by the reaction of glutaraldehyde with fructose-modified chitosan. Various factors that influence the preparation were studied and the reaction conditions were optimized. Morphology of rat hepatocytes cultured on CMs was observed using phase contrast microscope and scanning electron microscope, and the metabolic activities were measured. Rat hepatocytes cultured on CMs retained the spherical shape as they have in vivo and had high metabolic activities. Fructose can enhance the metabolic activity of hepatocytes and the modified CMs are promising scaffold for hepatocytes attachment.展开更多
基金the National Basic Research Program of China(2006CB504100)the National Natural Science Foundation of China (30393131, 30771043)
文摘Objective：To investigate the characteristics of fat metabolism in rat skeletal muscle after hypobaric hypoxia acclimation. Methods： Sprague-Dawley rats were divided into 3 groups randomly： control group （H0）, hypoxic 5-day group （HS）, and hypoxic 15-day group （H15）. Animals of H5 and 15 groups were exposed to hypobaric hypoxia chamber simulating 5 000 m high altitude for 5 d or 15 d respectively, 23 h per day. H0 group stayed outside of chamber The level of fatty acid oxidation and uptake, and glucose oxidation were examined, and the level of non-esterified fatty acids （NEFA）, ATP and phosphocreatine （PCr） were also assayed in rat skeletal muscles. Results： The contents of ATP and PCr in H5 group were lower than those in H0 and H15 groups （P〈0.05）, while there was no significant difference between H0 and H15. Compared with H0, the blood NEFA level in all hypoxia groups was increased significantly （P〈0.05）. The muscle NEFA level in H15 group was greatly higher than that in H0 and H5 groups. The rates of fatty acid oxidation and uptake in H15 group were significantly higher than those in H0 and H5 groups （P〈0.05）, and the rate of glucose oxidation in all hypoxia groups was significantly decreased than that in H0 group （P〈0.05）. Conclusion： It is concluded that the enhanced fat oxidation may be one of the mechanisms in the maintenance of energy homeostasis after hypobaric hypoxic acclimation.
基金The Natural Science Foundation of China (No. 30070222)
文摘The fructose modified chitosan microcarries (CMs) were prepared by the reaction of glutaraldehyde with fructose-modified chitosan. Various factors that influence the preparation were studied and the reaction conditions were optimized. Morphology of rat hepatocytes cultured on CMs was observed using phase contrast microscope and scanning electron microscope, and the metabolic activities were measured. Rat hepatocytes cultured on CMs retained the spherical shape as they have in vivo and had high metabolic activities. Fructose can enhance the metabolic activity of hepatocytes and the modified CMs are promising scaffold for hepatocytes attachment.
