How Insulin Controls Blood Sugar

Insulin can promote the uptake and utilization of glucose by tissues throughout the body and inhibit the breakdown of glycogen and gluconeogenesis. Therefore, insulin has the effect of lowering blood sugar. When excessive insulin is secreted, blood sugar drops rapidly, and the brain tissue is most affected, which can cause convulsions, coma, and even insulin shock. On the contrary, insufficient insulin secretion or lack of insulin receptors often leads to increased blood sugar. If it exceeds the renal glucose threshold, sugar is excreted in the urine, causing diabetes. At the same time, due to changes in blood components (containing excessive glucose), it also leads to high blood pressure, coronary heart disease, retinal vascular disease and other diseases. Insulin lowers blood sugar as a result of multiple effects:

(1) Promote the cell membrane carriers of target cells in muscles, adipose tissues, etc. to transport glucose from the blood into cells. (2) Through covalent modification, the activity of phosphodiesterase is enhanced, the level of cAMP is reduced, and the concentration of cGMP is increased, thereby increasing the activity of glycogen synthase and reducing the activity of phosphorylase, accelerating glycogen synthesis and inhibiting glycogenolysis.

(3) Activate pyruvate dehydrogenase phosphatase to activate pyruvate dehydrogenase, accelerate the oxidation of pyruvate to acetyl-CoA, and accelerate the aerobic oxidation of sugars. (4) Inhibit gluconeogenesis by inhibiting the synthesis of PEP carboxykinase and reducing the raw materials for gluconeogenesis. (5) Inhibit hormone-sensitive lipase in adipose tissue, slow down fat mobilization, and increase tissue glucose utilization.

Adverse reactions to overdose

If too much insulin is injected during treatment, it will lead to hypoglycemia. When the poisoning is mild, it mainly affects the autonomic nervous system, manifested as hunger, dizziness, pallor, weakness and sweating, and may also have tremors and precordial discomfort.

Numbness of face and limbs, headache. When blood sugar drops further, it affects the central nervous system, causing dysphonia, diplopia, muscle tremors, ataxia, followed by coma and convulsions of varying degrees. This condition is the so-called insulin shock, which can be fatal if not treated in time.

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