Triglyceride anabolism.

(i) glyceride pathway

" with glycerides as the starting point, together with lipidCoA in > lipidyl transferase under the action of esterification to produce triglycerides.

(70,135,221); "> (ii) phospholipidic acid pathway

< p class"tt1" >phospholipidic acid, or 3 phosphoric acid 1,2 glycerides, is a common prescient for the synthesis of glyphosate. The intermediate product of glycolysis, phosphate, is hydroxypropytonone, which reduces the production of α phosphate glyceloride( or 3 phosphate glyceloride) under the action of glycerol phosphoric acid >> kinase catalyzed to produce α phosphate glyceal (due to fat and muscle > tissuelack of glyceroid kinase, so the use of ionized glyceroid).

α phosphate glycelin in lipids(acyl transferase), with the two molecules lipidCoA reaction to produce 3 phosphoric acid, 2 glycerides, or phosphatidic acid acid. In addition, phosphate hydroxypropylone can also not be converted to α phosphate glycelin, but first esterification, then reduced to produce hemolytic phospholipidic acid, and then esterified synthetic phospholipid acid.

phospholipidic acid in phospholipidic acid">phosphatase action, water interpretation released inorganic phosphoric acid, and converted to glycerides, it is the predecessor of triglycerides, only esterification can produce triglycerides.

triglycerides contain three fatty acids that can be the same or different, saturated or unsaturated fatty acids.

the synthesis speed of triglycerides can be affected byhormone such as insulin can promote the transformation of sugar into triglycerides.

because of insufficient insulin secretion or ineffectiveness of diabetics, not only can not make good use of glucose, but also glucose or some >amino acids" can not be used to synthesize fatty acids, but the performance of fat oxidation rate increased, ketone production too much, the result is weight loss. In addition, gluten gluten, adrenal corticosteroids, etc. also affect the synthesis of triglycerides.

(iii) different tissue triglyceride synthesis characteristics

different tissue cells triglyceride synthesis characteristics, the following mainly discusses the liver, adipose tissue and small intestine mucous membrane skin cell synthesis triglyceride characteristics.

< p class. "tt1" >1. The liver can use sugar, glyceroid and fatty acids as raw materials to synthesize triglycerides by phospholipidic acid. Fatty acids are sourced from fat-mobilized fatty acids, fatty acids produced by the transformation of sugars and amino acids, and exocal fatty acids from foods (short- and medium-chain fatty acids that are absorbed and absorbed by fat in food and then blooded into the liver, fatty acids produced by fat breakdown in residual particles of celiac particles).

liver cells containing lipid substances about 4-7%, of which triglycerides account for about 1/2, triglyceride content is too high will cause fatty liver, under normal circumstances, liver synthesis of triglycerides and phospholipids, cholesterol, lipoprotein together to form very low-density lipoprotein, secreted into the blood. If phospholipid synthesis disorder or lipoprotein synthesis disorder will affect triglyceride transport out of the liver, causing fatty liver.

< p class s "tt1" >In addition, if too many fatty acids enter the liver, the amount of synthetic triglycerides exceeds the ability to synthesize lipoproteins, but also can cause fatty liver.

2. Adipose tissue adipose tissue triglyceride synthesis is basically the same as the liver, the difference between the two is that adipose tissue can not use glyceroid, can only use sugar decomposition provided by α-phosphate glyceroid;

< p class ."tt1" >3. There are two ways to synthesize triglycerides in small intestine mucous membrane epithelocells. After meals, triglyceride hydrolysing in food produces free fatty acids and triglycerides. After absorption, triglycerides are synthesized by glycerides. These triglycerides are involved in the composition of celiac particles. This approach is the main feature of triglyceride synthesis in small intestine mucous membranes.

and in the case of hunger, small intestine mucous membranes can also use sugar, glycerin and fatty acids as raw materials, by phospholipidic acid synthesis of triglycerides, this part of triglycerides involved in very low-density lipoprotein composition. At this point, the synthetic raw materials and processes are similar to the liver.

< the characteristics of triglyceride synthesis > the three tissues can be summarized in the table below.

table 5-5 characteristics of triglyceride synthesis in different organizations

< td colspan s"6" >

small intestine mucous membrane epithelitis cells

the main synthesis pathway< td align "middle" > after meals liver . < td align is "middle" > adipose tissue . glyceride-ester pathway< "middle" >phospholipidic acid pathway "middle" "middle" >a-phosphate glyceride pathway< > sugar "middle" > no < "middle" > no. "middle" > can No main intermediate product align<< > align "middle" >phospholipidic acid< td align> "middle" >phospholipidic acid can triglycerides be stored No No "middle" . < td align is a "middle" > be . mobilization or secretion forms< td align< "middle" >td align" > very low density lipid protein< td align""middle" > very low density lipoproteinFFAglycerin< physiological function< td align""middle" > synthesized external TCsynthesic endo-TC synthesized endo-TCstore triglycerides

. Little is known about the regulation of triglyceride anabolism.

.