How carbon monoxide binds to hemoglobin and reacts

After carbon monoxide enters the human body through the respiratory tract, it combines with hemoglobin in the blood to form a stable carbon oxygen hemoglobin, which is distributed throughout the body with the blood flow, and the affinity of carbon monoxide and hemoglobin is 200 300 times greater than that of oxygen and hemoglobin, so it competes with oxygen for hemoglobin and binds firmly, resulting in a greatly reduced oxygen-carrying capacity of hemoglobin. Causes systemic hypoxemia. The human central nervous system is most sensitive to hypoxia, so when hypoxia, brain tissue is the first to be affected, resulting in brain dysfunction and cerebral edema, which is directly life-threatening.

Soon after entering the alveoli, it develops a strong affinity with hemoglobin (HB), causing hemoglobin to form carboxyhemoglobin (COHB), which prevents the combination of oxygen and hemoglobin. The affinity of hemoglobin to carbon monoxide is 200 300 times greater than that of oxygen, and the dissociation rate of carboxyhemoglobin is 3600 times slower than that of oxyhemoglobin. Once the concentration of carboxyhemoglobin increases, the function of hemoglobin to carry oxygen to the body's tissues will be hindered, which in turn affects the function of the central nervous system (brain) and heart muscle, which are most sensitive to insufficient oxygen supply, resulting in tissue hypoxia, which can cause people to have symptoms of poisoning.

Carbon monoxide hemoglobin carboxyhemoglobin hemoglobin conjugate with carbon monoxide (CO). Same as oxyhemoglobin, the Fe atom is 2valent and covalently binds to the 4 N of CO, porphyrin, and histidine residues of hemocytoplasm prion to form an octahedral structure. The affinity of hemoglobin and CO is greater than that of O2, so if the blood invades CO, even if the hemoglobin has bound to O2, CO will replace O2 and make hemoglobin lose its ability to transport oxygen.

This is known as carbon monoxide poisoning

monoxide

intoxic-ation）。The maximum absorption peaks for carbon monoxide hemoglobin are 570 nm and 542 nm. It has a brighter red color than oxyhemoglobin.

Other heme pigments can also often bind to CO to form the same compound. The heme monooxide protein has the characteristic of being dissociated by photo. This is what characterizes it.

Carbon monoxide binds to hemoglobin, which hinders the binding of hemoglobin to oxygen. It is not conducive to the circulation of oxygen molecules in the body.

Both oxygen and carbon dioxide can form unstable compounds with hemoglobin residue in red blood cells in the blood, which in turn releases oxygen or carbon dioxide. If hemoglobin encounters carbon monoxide, but produces a relatively stable compound, it lowers the ability of hemoglobin to transport oxygen to the tissues, thus suffocating and poisoning people or animals.

Carbon monoxide poisoning is caused by the binding of carbon monoxide to hemoglobin, which binds more than oxygen: 210 times.

CO is inhaled through the respiratory tract and combines with hemoglobin to form carboxyl air collision hemoglobin (COHB).The affinity of CO to hemoglobin is about 250 300 times that of oxygen, and the dissociation rate of COHb is 1 3600 times that of oxyhemoglobin (HBO2).

After CO poisoning, the formed COHB has poor binding ability to oxygen, which reduces the oxygen-carrying capacity of the blood and causes severe hypoxia in tissues, and CO can directly cause cell hypoxia.

This problem is felt in the physiology and pathophysiology of carbon monoxide.

The characteristics of the combination of oxygen and hemoglobin are the only ones

1) The binding reaction is fast, reversible, and does not need to be catalyzed by enzymes, and the direction of the reaction depends on the partial pressure of oxygen in the corresponding organs.

2) The ferric 2 ion of the blood red sock protein is still in its low iron form when combined with O2, and there is no ion valence change, so it is called oxygenation, not oxidation.

3) Different hemoglobins have different absorption capacity for different broad spectrum, so the color of blood is related to both the content of hemoglobin and the nature of hemoglobin.

Carbon monoxide can also bind to hemoglobin, which is 240 times more affinity than O2, and will compete for the position of O2, resulting in a decrease in hemoglobin oxygen loading, and the oxygen consumption in the blood supply of organs cannot be replenished, which is also the mechanism of CO poisoning.

1.No, during the rescue process, it is not possible to cause rapid dissociation of carboxyhemoglobin to normal levels, and only in the case of patient exchange transfusion.

2.After the death of the patient, there should be no oxygen inhalation in the body, the blood circulates to stop, and carbon monoxide binds easily to hemoglobin but is difficult to dissociate, so there is no rapid dissociation.

3.Forensic identification may be difficult in the case of exchange transfusion before death, and the signs of hypoxia will persist after death.

4.Now the medical community has identified death as the basis of brain death, "the pupil is dilated by 5mm, and the light reflex is lost" is also a sign of deep coma, but with the addition of "breathing, the heart pulse has stopped", it can be said that death, rescue is no longer of much significance.

5.Ineffective, the blood is no longer circulating.

6.It may be a long time, at room temperature, to complete the dissociation, I am afraid that the corpse has already decomposed.

Hemoglobin (HB) is formed by combining globin and heme ferrohein. The red color of the blood is due to the presence of heme in it. It can temporarily bind to oxygen molecules in the lungs or gills, and the Fe2+ in this molecule combines with oxygen to form oxyhemoglobin (HBO2) when the partial pressure of oxygen is high; When the partial pressure of oxygen is low, it is dissociated from oxygen, and oxygen is released from the tissues of the body to become reduced hemoglobin, thereby realizing the function of transporting oxygen.

And most of the carbon dioxide is not transported by hemoglobin, but by plasma. The amino group of hemoglobin can bind to CO2.

nbnh2 + co2 ==nbnhcooh ==nbnhcoo- +h+

The binding capacity is related to whether hemoglobin is oxygenated, and it is easy to bind in tissues and dissociate in alveoli, and this mode of transport accounts for only 7% of the amount of CO2

Nitric oxide also binds to hemoglobin in the human blood to form nitroso hemoglobin, which deprives the blood of its ability to transport oxygen. That is, it can cause poisoning.

Nitric oxide is a nitrogen oxide with the chemical formula NO, relative molecular weight, and the valency of nitrogen is +2. It is a colorless and odorless gas, a toxic gas that is difficult to dissolve in water. Since nitric oxide carries free radicals, this makes it chemically very reactive.

When it reacts with oxygen, it can form a corrosive gas - nitrogen dioxide (NO2), which can react with water to form nitric acid. [6] The equation is: 3NO2+H2O==2HNO3+NO.

Hemoglobin (HB) is a binding protein composed of globin and ferrous hemoglobin that transports oxygen and carbon dioxide.

Hemoglobin (Hb) is a major binding protein present in red blood cells, which accounts for 90% of the total protein in red blood cells, and is composed of globin peptide chain and ferrous hemoglobin (heme), whose main function is to transport oxygen and excrete carbon dioxide to all parts of the body.

The amount of hemoglobin, like the red blood cell count, reflects the body's ability to produce red blood cells and can help diagnose red blood cell-related diseases. The reference range for hemoglobin is 120 160 g L for adult males, 110 150 g l for adult females, and 170 200 g l for newborns.

An increase in hemoglobin of 170 g L in adult males and 160 g L in adult females is found in multiple routine blood tests. Increased hemoglobin can be divided into: Relative increase: a decrease in plasma volume, resulting in a relative increase in red blood cell volume, which is seen in severe vomiting, diarrhea, profuse sweating, extensive burns, chronic adrenal insufficiency, diabetes insipidus, hyperthyroidism crisis, diabetic ketoacidosis, etc.

Absolute increase: increased erythropoietin or increased number of red blood cells in the blood, seen in obstructive emphysema, cor pulmonale, cyanotic congenital heart disease, renal cancer, hepatocellular carcinoma, ovarian cancer, renal embryoma tease, adrenocortical adenoma, uterine fibroids, hydronephrosis, polycystic kidney disease, polycythemia vera, etc., as well as plateau residents and normal neonates.