What is blood sugar

The glucose contained in the blood is called blood sugar. It is the form in which sugar is transported in the body.

There are 3 main ways in which blood sugar comes from in normal people.

①After meals, the sugar in food is digested into glucose and absorbed into the bloodstream, which is the main source of blood sugar. ② Fasting blood glucose from the liver, the liver stores hepatic glycogen, fasting hepatic glycogen decomposition into glucose into the blood. ③Protein, fat and lactic acid produced from muscle can be turned into glucose through the process of gluconeogenesis.

There are five main ways in which blood glucose goes in normal people.

①The main way of blood glucose is oxidized and decomposed into carbon dioxide and water in all tissues and cells of the body, while releasing a large amount of energy for the body to use and consume. ② Into the liver into hepatic glycogen storage. (iii) Into the muscle cells into muscle glycogen storage. ④Transforms into fat and stores it. ⑤Transformed into cellular components.

Blood glucose can be measured by glucose oxidase method, o-toluidine method and Folin-Wu method, and the first two methods are mostly used in domestic hospitals. Folin-Wu method has tended to be eliminated. Normal fasting plasma glucose is 3.9-6.1mmol/L (glucose oxidase method).

The practical significance of fasting blood glucose

The human body's blood glucose has a certain range of fluctuation at different times, and the fluctuation of blood glucose is mainly affected by diet and exercise. Different times of blood glucose represent different meanings, the patient in the fasting state of the blood glucose content, can reflect the level of the base case, because at this time has been excluded from the impact of diet on its. In the past, the level at this time of day was mostly used for clinical assessment and was the most commonly used type of test. The practical significance of testing fasting blood glucose is mainly in these areas:

1. A diagnosis of diabetes can be made if the fasting blood glucose level exceeds 7.0 mmol/liter.

2. A fasting blood glucose level of more than 11.1 mmol/liter indicates minimal or lack of insulin secretion, or the body's insensitivity to insulin. At the same time, it also suggests that the drug does not work well in the body, because when the blood glucose level exceeds 11.1 mmol/liter, the hypoglycemic effect of the drug will be reduced and weakened.

3, fasting whole blood glucose content of about 6.5 mmol / liter, plasma glucose content of about 6.0 mmol / liter, suggesting that further testing of glucose tolerance test, in order to confirm the diagnosis of diabetes mellitus.

Talking about the effects of blood glucose on the human body

Blood glucose is the glucose contained in the blood, and the blood glucose value indicates the concentration of glucose in the blood. Sugars are carbohydrates, and normal levels of blood sugar are extremely important for the physiological functions of the body's tissues and organs. Normal blood glucose fluctuates within a certain range, with a fasting blood glucose of 3.4-6.2 mmol/L (60-110 mg/dL) and a blood glucose of no more than 7.8 mmol/L (140 mg/dL) 2 hours after a meal. Glucose is necessary for the body, but too high or too low blood glucose will have certain effects on the body, some even lifelong and fatal, so maintaining the appropriate blood glucose concentration is what the organism needs. The following is a discussion of the effects of high and low blood sugar on the human body.

(I) High blood sugar

Is high blood sugar good for the human body? It should be said that short-term, transient hyperglycemia does not cause serious damage to the human body, the human body in a state of stress or emotional excitement, high tension, or a time to eat a large amount of sugar, there can be a transient hyperglycemia, and then, the blood glucose level in the body's various adjustments will gradually return to normal. Long-term hyperglycemia is common in diabetes mellitus, which is a systemic metabolic disorder caused by the absolute or relative insufficiency of insulin in the blood and the reduced sensitivity of target cells to insulin. Long-term hyperglycemia can lead to pathological changes in organs and tissues throughout the body, and the common ones are:

(1) The concentration of glucose in the blood is very high, but there is a lack of insulin, and glucose can't enter the target cells to be utilized, and the tissue cells lack glucose. is utilized, the lack of glucose in tissue cells, fat and protein decomposition is accelerated.

(2) The walls of capillaries throughout the body are thickened and the lumen is thinned, so it is not easy for red blood cells to pass through, and the tissue cells are deprived of oxygen.

(3) Glomerulosclerosis and necrosis of renal papillae occur in the kidneys.

(4) The fundus retinal capillaries appear microangiomas, fundus hemorrhage, oozing, etc.

(5) Degeneration of nerve cells and segmental demyelinating lesions of nerve fibers.

(6) Multiple atherosclerosis of the heart, brain, and lower extremities. Hyperglycemia is often accompanied by hyperlipidemia, and atherosclerosis of the coronary arteries, cerebral vessels, and lower extremities occurs earlier and is more severe than in normal people.

The above pathologic changes will cause the body to appear a variety of diabetic comorbidities, thus affecting the patient's quality of life, serious disability, death. Therefore, diabetic patients should be treated promptly.

(2) Hypoglycemia

Hypoglycemia is a syndrome characterized by sympathetic overexcitation and cerebral dysfunction due to a sudden drop in blood glucose below 2.8 mmol/L (50 mg/dL) caused by a variety of reasons. Due to the rapid drop in blood glucose, patients often experience hunger, nausea, vomiting, weakness, weakness, nervousness, anxiety, palpitations, cold sweats, pallor, tremor of the hands and feet, etc.; when blood glucose drops further, patients may experience trance, drowsiness, convulsions, coma; long-term and severe hypoglycemia can cause brain damage, such as coma for more than 6 hours, which can result in irrecoverable brain damage, and then cause death.

The most common cause of hypoglycemia is overdose or improper use of insulin and sulfonylureas by diabetic patients; elderly diabetic patients are prone to hypoglycemia before lunch or dinner even if their condition is stable and untreated.

For the prevention of hypoglycemia, first of all, the injection of insulin within 30 minutes to eat, when the activity increases, a small amount of food in a timely manner, go out to work to pay attention to eat on time, taking sulfonylurea hypoglycemic drugs patients should also be timely meal; secondly, the injection of mixed insulin patients, especially pay attention to eat dinner on time and before going to bed, to eat more staples or eggs, dried tofu, etc.; thirdly, bring along with you Some sugar cubes, cookies, etc., in case of hypoglycemic reaction.

When the acute attack of hypoglycemia:

1, the reaction is light, conscious patients, with white or brown sugar 25-50 grams of warm water or drink other sugary drinks; slightly heavier eat buns, bread or cookies 25 grams, or fruit 1-2, generally 10 minutes after the reaction can disappear.

2, hypoglycemic reaction is more serious, and not very clear, can be placed in the patient's mouth sugar or brown sugar, so that it is dissolved and swallowed; or adjusted into a syrup, slowly fed. If the sugar is still not awake for 10 minutes, it should be immediately sent to a nearby hospital for resuscitation.

3, the hypoglycemic coma patients, should be immediately injected intravenously 50% glucose 40 ml, and given oxygen, can soon be effective, or intramuscular injection of hyperglycemia 1 mg, within 15 minutes consciousness should be awake. After awake, the patient must be given sugar water, etc., to prevent the next reactive hypoglycemia.

Evan Essay 2000/9/9

An overview of blood glucose regulation:

Positive people's blood glucose stays in a very narrow range. In the unfed state before breakfast, blood glucose is about 80 ~ 90 mg / dl. Regulatory mechanisms:

(1) The liver is an extremely important glucose buffering system. When blood glucose is extremely high after a meal, insulin secretion increases so that almost two-thirds of the glucose absorbed from the intestine is deposited in the liver as hepatic glycogen. Over the next few hours, when both blood glucose and insulin decrease, the liver releases these stores back into the bloodstream. In this way, the liver reduces fluctuations in blood glucose by up to three times. In fact, people with severe liver disease are unable to keep their blood glucose levels within a narrow range.

(2) Insulin and glucagon are extremely important feedback systems that act separately to maintain normal blood glucose levels. High blood glucose stimulates insulin secretion and low blood glucose stimulates glucagon secretion. Under normal circumstances, the insulin system is much more important than the glucagon system. However, glucagon is important in times of glucose deficiency and when glucose is needed in large quantities, such as during exercise.

(3) Hypoglycemia also directly stimulates the inferior colliculus, which excites the sympathetic nerves and the adrenal glands to release epinephrine. Epinephrine causes the liver to release further glucose. This also prevents extreme hypoglycemia from occurring.

(4) If the hypoglycemia is prolonged for hours or days, growth hormone and cortisol are secreted to inhibit the use of glucose by cells throughout the body to ameliorate the hypoglycemia.

Importance of blood glucose regulation:

Some may ask: What is the importance of keeping blood glucose constant? The vast majority of tissues could just as easily switch to fatty acids for energy in the absence of glucose anyway. The answer is this: Glucose is the only fuel available to the brain, the omentum, and the germinal epithelium of the gonads. It is no wonder that blood glucose must always be kept constant to keep them supplied with nutrients. Between meals, the vast majority of glucose synthesized by the liver's gluconeogenesis is supplied to the brain.

On the other hand, too much glucose is not good for three reasons: (1) Too much glucose increases the osmotic pressure of the extracellular fluid, resulting in cellular dehydration. (2) High blood sugar causes a lot of glucose to be lost in the urine. (3) This in turn causes osmotic diuresis, a loss of water and electrolytes.

What are the daily changes in blood glucose in a normal person?

Under normal physiological conditions, the sources and destinations of blood glucose maintain a dynamic balance, so the concentration of blood glucose is relatively constant. It can maintain the normal glucose metabolism of tissue cells, which is important to ensure the normal physiological activities of tissues and organs, especially brain tissues.

After a meal, normal people's blood glucose reaches 7.8-8.9mmol/L in about 1 hour, and the maximum is not more than 10.0mmol/L. This is due to the gradual increase of glucose absorbed from the intestinal tract after a meal, which leads to hyperglycemia, and the high glucose stimulates the pancreatic β-cells to increase the secretion of insulin, which reduces the anabiosis of glucose by inhibiting the decomposition of hepatic glucose to promote glucose to be hepatic glucose and enter the tissues such as muscle, fat, etc., thus blocking the blood sugar metabolism of organs and especially brain tissues. muscle, fat and other tissues, thus blocking the source of blood glucose, accelerating the utilization of blood glucose, so that the blood glucose after meals is not excessively high. In normal people, 2 hours after meals, blood glucose and plasma insulin fall to the level before meals. This means that if a normal person eats three meals a day, then within 24 hours there will be 6 hours of elevated blood glucose, and the remaining 18 hours of blood glucose are at the fasting level.

Normal people fasting does not appear hypoglycemia, but to maintain blood glucose in the normal range (normal people fasting plasma glucose for 3.9 ~ 6.1mmol / L). This is because fasting insulin secretion is reduced, pancreatic glucagon secretion increases, promoting the decomposition of hepatic glycogen and gluconeogenesis, so that blood glucose increases; at the same time, growth hormone secretion increases, inhibiting the use of blood glucose by the body's various tissues and cells, thus ensuring that the most important organ of the human body - the brain to get a full supply of blood glucose.

Why can normal people maintain a certain level of blood sugar?

Normal people's blood sugar can maintain a certain level, mainly relying on the liver, hormones and nervous system regulation. (1)Liver: Under normal physiological condition, when blood sugar rises, glucose enters into liver cells, which synthesize a large amount of glucose into glycogen and store it for "famine"; part of the glucose synthesizes into fat, so that glucose entering into the blood circulation will not be excessive. Low blood sugar during starvation is a serious problem for brain and blood cells. Brain and blood cells have no glycogen reserves of their own and must take glucose from the blood to maintain their function, which becomes dysfunctional once blood glucose levels are low. Hepatocytes can generate glucose to be sent into the blood circulation to raise the blood glucose level through two pathways: glycogenolysis and gluconeogenesis. (2) Hormones: ① Insulin: It is the only hormone in the body that lowers blood sugar. It promotes the uptake and utilization of glucose by tissue cells, promotes the synthesis of glucose into glycogen by liver cells and muscle cells, promotes the conversion of sugar into fat, and inhibits the isomerization of sugar. ② Pancreatic glucagon: It can promote hepatic glycogen decomposition and reduce the utilization of glucose and increase blood glucose. ③Adrenaline: It can promote the decomposition of hepatic glycogen and the enzymolysis of myo-glycogen, thus raising blood glucose. Glucocorticoid: It can promote glucose isomerization in the liver and inhibit glucose uptake by muscle and adipose tissue, thus raising blood glucose level. ⑤ Growth hormone: inhibits the utilization of glucose by muscle and adipose tissue, and promotes sugar xenobiosis in the liver to raise blood glucose. A variety of hormones in the body complement each other, *** with the formation of a glucose metabolism regulation system, maintaining the dynamic balance of blood glucose. (3) Nervous system: The central nervous system secretes epinephrine and norepinephrine through the sympathetic nervous system or the adrenal medulla, inhibiting insulin secretion and raising blood glucose. The central nervous system increases insulin secretion through the parasympathetic nerves. Various stress states such as acute myocardial infarction, cerebrovascular accident, trauma, surgery, anesthesia, severe infection, pain, shock and nervousness and anxiety can increase the secretion of adrenocorticotropic hormone, glucagon, epinephrine and norepinephrine, and increase the blood glucose temporarily.

Normal human blood glucose in the liver, hormones and nervous system regulation, fluctuations within a certain range, fasting blood glucose 3.9 ~ 6.1 mmol / L, 2 hours after the meal blood glucose does not exceed 7.8 mmol / L, here referred to the blood glucose are venous plasma glucose concentration.