Liver detoxification

By | April 23, 2012

Liver detoxification function, many substances such as inside and outside the human body produced during metabolism of various biologically active substances, metabolic end products, from in vitro a variety of foreign objects into the body (such as drugs, toxins, food additives, etc.) and absorbed from the intestine corruption and other products will enter the liver. Most of these substances is not only the body can not be used, and some substances also produce toxic side effects on the body. Therefore, the body must be excreted directly or after biotransformation them excreted. Biological transformation processes in the liver plays an important role in transforming the core of biological organs. Liver biotransformation process is through the first phase reaction or (and) the second reaction, the fat-soluble substance obtained strong polar groups to increase the water-soluble to facilitate discharge from the kidney.
The first phase reactions, including oxidation, reduction and hydrolysis reactions. Enzymes involved in oxidation reactions are mainly three kinds: in the liver cells and single microsomal oxidases (also known as mixed function oxidase enzymes such as cytochrome P450), mitochondrial oxidative enzymes in the gel and the cytoplasm and mitochondria The dehydrogenase; in reduction of the enzyme is mainly located in the liver microsomes nitroreductase and azo reductase; mainly by esterase hydrolysis, amide enzyme and glycoside hydrolase enzymes that esters were , amides, glycosides hydrolysis. Most of the first phase reaction is mainly in the microsomes of liver cells. Of course, there are many substances even after the first reaction, but the polarity change is not big enough to be a second further reaction.
Liver detoxification function, the second reaction is the binding reaction. Intrahepatic many strong polar substances can be directly combined with the material that is homogeneous. Such as glucuronic acid, sulfuric acid, methyl, acetyl, etc. combined with some substance is required after the first reaction after the first phase and the binder. Treatment of these substances by the liver, increased water solubility, biological activity or toxicity reduction, easy with the bile or excreted by the kidneys, so the process of integration, also known as detoxification.
In addition to biotransformation, the liver can excrete the drug from the bile, the molecular weight is larger than 400_500 who, directly from the bile excretion, the molecular weight of less than 300 are excreted from the kidney into the blood.
Liver detoxification function, under normal circumstances, many drugs, toxic products such as corruption or intestinal biotransformation by the liver, its reduced toxicity or biological activity, so can the liver as a detoxification organ. But there are some substances, especially some of the drugs through biological transformation, but increased its activity or toxicity, such as the hypnotic chloral hydrate after reduction by the liver into trichloroethanol, to strengthen its hypnotic effect; isoniazid by acetylation turned to isonicotinic acid and acetyl hydrazine, acetyl hydrazine and intrahepatic covalently bound macromolecules, resulting in liver cell necrosis; some exogenous substances such as benzo liver by biological transformation is only a carcinogen.

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