de-Mello M A
Departamento de Educação Física, Instituto de Biociências, Universidade Estadual Paulista, SP, Brasil.
Braz J Med Biol Res. 1994 Oct;27(10):2461-6.
The effect of intrauterine and postnatal protein-calorie malnutrition on the biochemical ability to perform exercise was investigated in young male rats. Malnourished rats were obtained by feeding dams a low-protein (6%) casein-based diet prepared in the laboratory during pregnancy and lactation. Control rats received an isocaloric diet containing 25% protein. The low-protein diet contained additional starch and glucose. At 45 days of age, malnourished rats showed lower body weight, serum protein, albumin and glucose levels, hematocrit values and heart glycogen content but higher circulating free fatty acids and gastrocnemius muscle glycogen than control rats. In response to exercise (50 min of swimming), control rats displayed lower heart, gastrocnemius and liver glycogen levels whereas malnourished rats showed low glycogen levels only in the gastrocnemius muscle. Both control and malnourished rats showed high serum glucose and free fatty acid levels after exercise. In conclusion, protein-calorie malnutrition improved muscle glycogen storage but this substrate was broken down to a greater extent in response to exercise. Malnourished rats were able to perform exercise maintaining high blood glucose levels, as observed in control rats, perhaps as a consequence of the elevated availability of circulating free fatty acids.
研究了宫内和出生后蛋白质 - 热量营养不良对年轻雄性大鼠运动生化能力的影响。通过在孕期和哺乳期给母鼠喂食实验室配制的低蛋白（6%）酪蛋白基饮食来获得营养不良的大鼠。对照大鼠接受含25%蛋白质的等热量饮食。低蛋白饮食含有额外的淀粉和葡萄糖。在45日龄时，营养不良的大鼠体重、血清蛋白、白蛋白和葡萄糖水平、血细胞比容值以及心脏糖原含量均低于对照大鼠，但循环游离脂肪酸和腓肠肌糖原高于对照大鼠。运动（50分钟游泳）后，对照大鼠心脏、腓肠肌和肝脏的糖原水平降低，而营养不良的大鼠仅腓肠肌糖原水平降低。运动后，对照大鼠和营养不良的大鼠血清葡萄糖和游离脂肪酸水平均升高。总之，蛋白质 - 热量营养不良改善了肌肉糖原储存，但该底物在运动时分解程度更大。如在对照大鼠中观察到的那样，营养不良的大鼠能够在运动时维持高血糖水平，这可能是循环游离脂肪酸可用性增加的结果。
