Glucose hormonal regulation

C. Blood glucose is regulated by the hormones insulin, glucagon, and epinephrine. 

The Hormone Epinephrine Stimulates Glucose Production in Both Liver Cells and Muscle Cells The Hormonal Regulation of the Flux between Fructose-6-phosphate and Fructose-1,6-bisphosphate Is Mediated by Fructose-2,6-bisphosphate... 

Simpson, I.A. Cushman, S.W. (1989). Hormonal regulation of mammalian glucose transport. Ann. Rev. Biochem. 55,1059-1089. 

Hexokinase is an enzyme that is mentioned at an early point in most biochemistry courses, since this enzyme is required for the first step in the body s utilization of glucose. The promoter for the hexokinase gene is shown here. This promoter consists of about 160 base pairs, and contains a TATA box (AATAA underlined), a CCAAT box [also underlined), and a short sequence of DNA that is regulated by a hormone. The hormone-regulated sequence is CCACGTCA (underlined). This short sequence of DNA is one of many types of "response elements" that occur in the genome. Specifically, CCACGTCA is called the cyclic AMP response element, for reasons that are explained later. This response element occurs in the hexokinase promoter, just a few nucleotides beyond the CCAAT box (Osawa rf a., 1996) ... 

Hormones regulate intracellular metabolic processes. Insulin intensifies transfer (transport) of the glucose in the cell and decreases its level in the circulating blood. Glucagon increases the sugar level in the blood. The two hormones are synthesized by the pancreas. Antibodies discern foreign bodies in an organism. 

Figure 2S-I0 Hormonal regulation of blood glucose. Key +, stimulation —, inhibition. Cortisol, growth hormone, and epinephrine also antagonize the effect of insulin.

The concentration of glucose in blood is hormonally regulated. Fluctuations in blood glucose level (normally 60 to 90 mg/100 mb, or about 4.5 mM) due to dietary intake or vigorous exercise are counterbalanced by a variety of hormonally triggered changes in the metabolism of several organs. 

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