Positron emission tomography permits noninvasive measurement of regional glucose uptake in vivo in humans. We employed this technique to determine the effect of FFA on glucose uptake in leg, arm, and heart muscles. Six normal men were studied twice under euglycemic hyperinsulinemic (serum insulin approximately 500 pmol/liter) conditions, once during elevation of serum FFA by infusions of hepari...

Role of muscarinic receptor in the regulation of glucose uptake or lipolysis in adipose tissue remained unclear. In epididymal white adipose tissue (WAT) isolated from Wistar rats, we observed that acetylcholine (ACh) attenuated the insulin-stimulated glucose uptake and the release of glycerol from WAT in a concentration-dependent manner. Using the blockade of specific antagonists, both actions...

An intrinsic hypoglycaemic activity has been attributed to ACTH. This action of ACTH is essentially mediated by increased insulin secretion. In the present study, the direct action of ACTH on glucose uptake by pigeon hepatocytes has been studied by in vitro technique. The results have shown that ACTH has a direct influence on glucose uptake and this action is not additive in presence of insulin...

It is well established that insulin stimulation of glucose uptake in skeletal muscle cells is mediated through translocation of GLUT4 from intracellular storage sites to the cell surface. However, the established skeletal muscle cell lines, with the exception of L6 myocytes, reportedly show minimal insulin-dependent glucose uptake and GLUT4 translocation. Using C(2)C(12) myocytes expressing exo...

Physical training increases skeletal muscle insulin sensitivity. Since training also causes functional and structural changes in the myocardium, we compared glucose uptake rates in the heart and skeletal muscles of trained and untrained individuals. Seven male endurance athletes (VO2max 72 +/- 2 ml/kg/min) and seven sedentary subjects matched for characteristics other than VO2max (43 +/- 2 ml/k...

The study investigated the role of adrenergic receptors in glucose, fructose-, and galactose- induced increases in intestinal glucose uptake. Experiments were carried out on fasted male anaesthetized Nigerian local dogs divided into seven groups (with five dogs per group). Group I dogs were administered normal saline and served as control. Dogs in groups II, III and IV were intravenously infuse...

both insulin-dependent and non-insulin-dependent diabetes. One of the major factors regulating glucose uptake into muscle is the quantity of glucose transporter (GLUT) protein on the cell surface. In muscle and adipocytes, GLUT1 mediates basal or nonstimulated transport, whereas GLUT4, the insulin-responsive GLUT, facilitates increased glucose transport in the presence of insulin. Membrane GLUT...

Effects of genetic selection for high wheel-running activity (17th generation) and access to running wheels on skeletal muscle glucose uptake were studied in mice with the following treatments for 8 wk: 1) access to unlocked wheels; 2) same as 1, but wheels locked 48 h before glucose uptake measurement; or 3) wheels always locked. Selected mice ran more than random-bred (nonselected) mice (8-wk...

The aim of this study was to investigate the effects of insulin on glucose uptake in lactating bovine mammary epithelial cells (BMEC). Primary BMEC were cultured in Dulbecco's modified Eagle's medium/nutrient mixture F-12 and treated with different levels of insulin (0, 5, 50, and 500 ng/mL) for 48 h after a 24-h starvation without fetal calf serum. Compared with the control cells (0 ng of insu...

In the present study, the relationship between the pattern of electrical stimulation and glucose uptake was investigated in slow-twitch muscles (soleus) and fast-twitch muscles (epitrochlearis) from Wistar rats. Muscles were stimulated electrically for 30 min in vitro with either single pulses (frequencies varied between 0.8 and 15 Hz) or with 200-ms trains (0.1-2 Hz). Glucose uptake (measured ...