Glucose utilization in muscle fiber types: use of the partial pancreatectomized rat model to distinguish effects of glucose and insulin on insulin resistance.
Glucose utilization in muscle fiber types: use of the partial pancreatectomized rat model to distinguish effects of glucose and insulin on insulin resistance.
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DOI：
10.1006/mgme.1998.2736
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发表时间：
1998-09
影响因子：
3.8
通讯作者：
N. Rizk;D. Meier;D. Pastorek;G. Krakower;A. Kissebah
中科院分区：
文献类型：
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作者：
N. Rizk;D. Meier;D. Pastorek;G. Krakower;A. Kissebah
我们使用了部分胰腺切除的输注模型，以研究葡萄糖和胰岛素对大鼠骨骼肌胰岛素抵抗的单独和联合作用。输注葡萄糖或胰岛素可产生高血糖、高胰岛素血症或两者兼有的动物。通过2-脱氧葡萄糖摄取研究慢性高血糖和高胰岛素血症对糖酵解和氧化肌纤维中基础和胰岛素介导的葡萄糖利用指数的单独和联合作用。高血糖使基础葡萄糖利用指数降低了49%，高胰岛素血症降低了55%，而高血糖+高胰岛素血症使2-脱氧葡萄糖摄取降低了69%。在高血糖状态下，最大胰岛素刺激利用率仅降低28%，但在高胰岛素血症状态下降低81%。为了评估单个肌纤维的利用率，在不同纤维组成的三种组织中检查了摄取。慢收缩氧化比目鱼肌表现出更大的基础摄取比快收缩腓肠肌（糖酵解）和四头肌（氧化）肌肉。此外，基础（虽然不是最大的胰岛素刺激）葡萄糖利用的快缩肌纤维的慢性葡萄糖和胰岛素的影响，在更大程度上比慢缩比目鱼肌，表明慢性高血糖症更容易沉淀胰岛素抵抗的快缩肌。肌纤维类型之间葡萄糖代谢的显着差异表明，混合肌肉中胰岛素抵抗研究的结果可能会根据其纤维组成而有所偏差。
We have used the partially pancreatectomized infusion model in order to examine individual and combined effects of glucose and insulin on insulin resistance in rat skeletal muscles. Infusing glucose or insulin can produce animals which are hyperglycemic, hyperinsulinemic, or both. Individual and combined effects of chronic hyperglycemia and hyperinsulinemia on basal and insulin-mediated glucose utilization indices in glycolytic and oxidative muscle fibers were examined by 2-deoxyglucose uptake. Hyperglycemia reduced the basal glucose utilization index by 49% and hyperinsulinemia by 55%, while combined hyperglycemia + hyperinsulinemia diminished 2-deoxyglucose uptake by 69%. Maximally insulin-stimulated utilization was diminished only 28% under hyperglycemia but by 81% in the hyperinsulinemic state. In order to assess utilization in individual muscle fibers, uptake was examined in three tissues of differing fiber composition. The slow-twitch oxidative soleus muscle demonstrated greater basal uptake than the fast-twitch gastrocnemius (glycolytic) and quadriceps (oxidative) muscles. In addition basal (though not maximally insulin-stimulated) glucose utilization in the fast-twitch fibers was affected by chronic glucose and insulin to a greater extent than the slow-twitch soleus muscle, indicating that chronic hyperglycemia is more likely to precipitate insulin resistance in fast-twitch muscles. Significant differences in glucose metabolism among muscle fiber types suggests that results from insulin resistance studies in mixed muscles may be skewed according to their fiber composition.