salivary mucin

The proteins in saliva are mainly mucin, and other proteins are low in content. To date, more than ten kinds of salivary proteins and enzymes have been discovered as genetic markers, which have certain significance for human genetics and forensic research. Mucin is the main organic component in mucus. Covers all oral mucosal surfaces. There are two different types of mucin in saliva, high molecular weight mucin and low molecular weight mucin, which differ in their structure and biological properties. The former has a higher carbohydrate content and the latter is relatively lower. Basic Information Specialist classification: oral examination classification: body fluid examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: When it is reduced, it may cause inflammation of the oral mucosa. Normal value: Salivary mucin: 0.91-1.81g/L Above normal: Rare. negative: Positive: Tips: Care must be taken when pouring the supernatant, so that the sediment cannot be lost, otherwise the result will be low. Normal value (1.36 ± 0.450) g ​​/ L. Clinical significance The main physiological effects of mucin: 1. Fight against dryness and protect the oral mucosa from external damage. Mucin prevents the passage of potentially dangerous substances through the mucosa, prevents acid and degrading enzymes from invading the oral mucosa, and inhibits the dissolution of certain proteins. 2, lubrication, saliva lubrication is mainly attributed to the terminal sialic acid. 3. Resistance to harmful microorganisms, salivary mucin carbohydrates play a major role in the non-immune clearance of microorganisms, which may be related to enzymes and/or phytohemagglutinin located on the surface of microorganisms. When reduced, it may cause inflammation of oral mucosa. Low results may be diseases: duodenal adenocarcinoma, varicose veins of the lower extremities 1. Mucin is a complex protein composed of a mucopolysaccharide and a protein molecule, which is mainly present in the α1 and α2 globulin fractions. Its mucopolysaccharide is often composed of glucosamine, galactose, mannose, fucose and citric acid. The mucin component is complex, and the classification and naming are not consistent. Meyer classifies the complex of sugar and protein by the content of aminohexose, a glycoprotein with an aminohexose content greater than 4% and a glycoprotein with less than 4%. 2. The tyrosine content in mucin is 4.2%, so the two reporting methods can be converted to each other. 3. After adding perchloric acid to precipitate protein, it should be placed for 10 minutes and then filtered. After adding phosphotungstic acid, it also needs to be placed for 10 minutes before centrifugation. When decanting the supernatant, care must be taken to prevent the sediment from being lost, otherwise the result will be low. Inspection process 1. Saliva (diluted) 0.5ml, add 154mmol/L sodium chloride 4.5ml, mix well, add 2.5ml/L perchloric acid solution 2.5ml, stand still for 10min, filter or centrifuge with quantitative filter paper. 2. Take 2.5 ml of the filtrate, add 0.574 ml of 17.74 mmol/L phosphotungstic acid, mix for 10 min, centrifuge at 3000 r/min for 10 min, decanrate the supernatant and drain. 3. Add 2 ml of phosphotungstic acid solution, suspend the sediment, centrifuge the same method, and then drain the supernatant and drain. Take the precipitate for later use. 4. Mix well, set to 37 ° C water bath for 15 min, remove at 650 nm, light path 1.0 cm, zero with blank tube, read the absorbance of each tube. Not suitable for the crowd Those without examination indications should not be tested. Adverse reactions and risks no.