Rosdahl H, Lind L, Millgård J, Lithell H, Ungerstedt U, Henriksson J
Department of Physiology and Pharmacology, Karolinska Institute, University College of Physical Education and Sports, Stockholm, Sweden.
Diabetes. 1998 Aug;47(8):1296-301. doi: 10.2337/diab.47.8.1296.
The effect of an euglycemic-hyperinsulinemic glucose clamp (94 +/- 5 microU/ml) on blood flow and glucose extraction fraction in human skeletal muscle and adipose tissue was investigated. Limb blood flow was measured by venous occlusion pletysmography and tissue blood flow by the microdialysis ethanol technique. Insulin infusion resulted in an increased blood flow in the calf and forearm (64 and 36%, respectively; P < 0.01) but not in the studied muscles of these limbs (ethanol outflow-to-inflow ratio: m. gastrocnemius 0.144 +/- 0.009 to 0.140 +/- 0.011, NS; m. brachioradialis 0.159 +/- 0.025 to 0.168 +/- 0.027, NS). This was accompanied by an increased extraction fraction of glucose, as measured by an increased arteriovenous difference over the forearm (0.16 +/- 0.04 to 0.70 +/- 0.10 mmol/l; P < 0.001) and by an increase in the estimated arterial-interstitial glucose difference in the gastrocnemius (0.82-1.42 mmol/l) and brachioradialis muscle (0.82-1.97 mmol/l). The blood flow in adipose tissue was significantly increased during insulin infusion, as evidenced by a decreased ethanol outflow-to-inflow ratio (0.369 +/- 0.048 to 0.325 +/- 0.046; P < 0.01). This was accompanied by an unchanged concentration of glucose in the dialysate (-2.6%, NS). In summary, during physiological hyperinsulinemia 1) a blood flow increase was detected in the calf and forearm, but not in the studied muscles of these limbs; 2) the blood flow increased in the subcutaneous adipose tissue; and 3) the estimated arterial-interstitial glucose difference increased in both muscles studied and was larger in the forearm muscle than the arteriovenous glucose difference over the forearm. The present study shows that microdialysis is a useful tool to obtain tissue-specific information about the effect of insulin on blood flow and glucose extraction in human skeletal muscle and adipose tissue.
研究了正常血糖 - 高胰岛素血糖钳夹（94±5微单位/毫升）对人体骨骼肌和脂肪组织血流及葡萄糖摄取分数的影响。通过静脉阻塞体积描记法测量肢体血流，通过微透析乙醇技术测量组织血流。胰岛素输注导致小腿和前臂血流增加（分别增加64%和36%；P<0.01），但这些肢体的所研究肌肉血流未增加（乙醇流出与流入比率：腓肠肌从0.144±0.009至0.140±0.011，无显著差异；桡侧腕屈肌从0.159±0.025至0.168±0.027，无显著差异）。这伴随着葡萄糖摄取分数增加，通过前臂动静脉差值增加得以测量（从0.16±0.04至0.70±0.10毫摩尔/升；P<0.001），以及腓肠肌（从0.82 - 1.42毫摩尔/升）和桡侧腕屈肌（从0.82 - 1.97毫摩尔/升）估计的动脉 - 组织间隙葡萄糖差值增加。胰岛素输注期间脂肪组织血流显著增加，这通过乙醇流出与流入比率降低得以证明（从0.369±0.048至0.325±0.046；P<0.01）。这伴随着透析液中葡萄糖浓度无变化（-2.6%，无显著差异）。总之，在生理性高胰岛素血症期间：1）小腿和前臂血流增加，但这些肢体的所研究肌肉血流未增加；2）皮下脂肪组织血流增加；3）所研究的两块肌肉中估计的动脉 - 组织间隙葡萄糖差值均增加，且前臂肌肉中的该差值大于前臂动静脉葡萄糖差值。本研究表明，微透析是获取关于胰岛素对人体骨骼肌和脂肪组织血流及葡萄糖摄取影响的组织特异性信息的有用工具。
