Metabolism, effect of insulin

FIGURE 23.22 The metabolic effects of insulin. As described in Chapter 34, binding of insulin to membrane receptors stimulates the protein kinase activity of the receptor. Subsequent phosphorylation of target proteins modulates the effects indicated. 

Table 11.1 Some metabolic effects of insulin. These effects are generally countered by other hormones (glucagon and, in some cases, adrenaline). Hence, the overall effect noted often reflects the relative rates of these hormones present in the plasma...

Insulin aspart is absorbed nearly twice as fast as regular insulin. In addition to binding to the insulin receptor, insulin aspart also binds to the insuUnlike growth factor (IGF-1) receptor, which shares structural homology with the insulin receptor. However, at physiological and pharmacological levels, the metabolic effects of insulin aspart predominate. Both lispro insulin and insulin aspart have relatively fast onsets and short... 

D) Glucagon is a hormone that counteracts many of the metabolic effects of insulin. 

Study Questions 23. Metabolic Effects of Insulin and Glucagon... 

UNIT V Integration of Metabolism Chapter 23 Metabolic Effects of Insulin and Glucagon 305 Chapter 24 The Feed/Fast Cycle 319 Chapter 25 Diabetes Mellitus 335 Chapter 26 Obesity 347 Chapter 27 Nutrition 355 Chapter 28 Vitamins 371... 

RosdahlH, Hamrin K, Ungerstedt U, Henriksson J. A microdialysis method for the in situ investigation of the action of large peptide molecules in human skeletal muscle detection of local metabolic effects of insulin. International Journal of Biological Macromolecules 2000, 28, 69-73. 

Insulin-like growth factors (IGFs) or somatomedins are in a family of polypeptides with growth-promoting activities and which can also modulate some of the shortterm metabolism effects of insulin [47,48]. 

In addition, the metabolic effects of insulin ultimately increase fetal oxygen consumption. The circulation of the fetus is unique specifically, because blood in the fetal descending aorta contains a portion of venous return after tissue perfusion, the increased rate of consumption of oxygen by fetal tissues decreases the arterial oxygen concentration of the fetus. The fetal tissues supplied by this circulation (which include most of the mass of the fetus) are then at risk for inadequate tissue oxygenation. 

Tab. 3.10 Metabolic effects of insulin and contra-insulin hormones (glucagon, catecholamines) in the liver...

Metabolic Effects of Insulin. Insulin has pronounced effects on the metabolism of carbohydrates, lipids, and proteins. The major tissues affected by insulin are muscle (cardiac and skeletal), adipose ti.ssue, and liver. The kidney is much less responsive, and others (e.g.. hrain tis.sue and red blood cells) do nut respond at all. The actions of insulin arc highly complex and diverse. Because many of the actions of insulin are mediated by. second messengers, it is difficult to distinguish between its primary and secondary actions. 

The protein-anabolic and protein-sparing actions of GH require the metabolic effects of insulin, glucagon, cortisol, and thyroid hormone in the unstressed individual. These actions depend on fine-tuned control of GH release, which is achieved mainly by substrate feedback to the hypothalamus (Figure 31-5). 

According to this mechanism, Akt kinase regulates central metabolic pathways of the cell. It is a major regulator in insulin-dependent metabolic pathways. The PI3-kinase/Akt pathway is activated by insulin and thereby mediates many of the metabolic effects of insulin, including glucose transport, lipid metabolism, glycogen synthesis and protein synthesis (see Section 1.5.6). Furthermore, by phosphorylating pro-... 

Table 43.1 Summary of main metabolic effects of insulin, glucagon and adrenaline...

Factors Affecting Insulin Secretion Structure and Synthesis of Insulin Insulin Transport and Breakdown Metabolic Effects of Insulin Carbohydrate Metabolism 510 Muscle Liver... 

Although many metabolic effects of insulin on carbohydrate metabolism have been described in detail, discussion of the primary site of action of the hormone has often been omitted. 

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