Blood glucose concentration regulation

Storage and utilization of tissue glycogen, maintenance of blood glucose concentration, and other aspects of carbohydrate metabolism are meticulously regulated by hormones, including insulin, glucagon, epinephrine, and the glucocorticoids. 

THE CONCENTRATION OF BLOOD GLUCOSE IS REGULATED WITHIN NARROW LIMITS... 

P cells of the pancreatic islets in combination with atoms of zinc, but when required to regulate blood glucose concentration, the prohormone is cleaved and functional insulin is released into the circulation along with the C-peptide. This example of post-translational processing is mediated by peptidases which are contained in the vesicles along with the proinsulin. The fusion of the secretory vesicles with the cell membrane and activation of the peptidase prior to exocytosis of the insulin are prompted by an influx of calcium ions into the P-cell in response to the appropriate stimulus. Similarly, catecholamines are synthesized and held within the cell by attachment to proteins called chromogranins. 

In addition to the common pathways, glycolysis and the TCA cycle, the liver is involved with the pentose phosphate pathway regulation of blood glucose concentration via glycogen turnover and gluconeogenesis interconversion of monosaccharides lipid syntheses lipoprotein formation ketogenesis bile acid and bile salt formation phase I and phase II reactions for detoxification of waste compounds haem synthesis and degradation synthesis of non-essential amino acids and urea synthesis. 

Figure 3.23 A sequence of processes explaining the role of glucokinase in the liver and fi-cells in regulation of the blood glucose concentration. The increase in the plasma insulin increases glucose uptake by muscle and decreases fatty acid mobilisation from adipose tissue which lowers the plasma fatty acid level which also increases glucose uptake (Chapter 12).

ROLE OF THE LIVER IN THE REGULATION OF THE BLOOD GLUCOSE CONCENTRATION... 

Role of the liver in the regulation of the blood glucose concentration... 

How these processes are regulated in response to changes in the blood glucose concentration is now considered. 

The role of glucagon and insulin in the regulation of glu-coneogenesis, along with other factors, is to maintain the blood glucose concentration in starvation. This is discussed in Chapter 12. 

B. Regulation of blood glucose concentration occurs initially through changes in its... 

As discussed in Chapter 5, the body regulates blood glucose concentration through the opposing actions of insulin versus glucagon and epinephrine. 

There are at least four independent sensors that monitor blood glucose concentration in the body and contribute to the overall regulation of food intake. 

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