alpha-hydroxybutyrate dehydrogenase

Α-hydroxybutyrate dehydrogenase (α-HBDH) is closely related to LDH. In fact, it is LDH isoenzyme type I. Because of its high affinity for α-ketobutyrate, α-ketobutyric acid is used. As a substrate, the activity of the LDH measured is specifically referred to as α-hydroxybutyrate dehydrogenase activity. The α-HBDH measurement methods mainly include colorimetry and continuous monitoring. Basic Information Specialist classification: cardiovascular examination classification: biochemical examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: Rare. Normal value: --hydroxybutyrate dehydrogenase (colorimetric method): 61-155U/L --hydroxybutyrate dehydrogenase (continuous monitoring method): 72-182U/L Above normal: 1. The activity of α-HBDH was significantly increased in myocardial infarction, and the maintenance time was longer than that of LDH. The ratio of LDH/α-HBDH (0.8～1.2) was lower than that of normal control (1.2～1.6). 2. Identify liver disease and heart disease. LDH can be elevated in liver disease and heart disease, but the activity of α-HBDH does not change much in liver disease, the ratio of LDH/α-HBDH can be increased to 1.6-2.5, and α-HBDH is significantly increased in heart disease. 3. When malnutrition, folic acid and vitamin B12 are deficient, α-HBDH activity may also increase. negative: Positive: Tips: Before the examination, the diet is light and alcohol is prohibited. Check for an empty stomach in the morning. Guarantee a good night's sleep. Normal value 1. Colorimetric method 61 to 155 U/L (37 ° C). 2, continuous monitoring method 72 ~ 182U / L. Clinical significance The activity of α-HBDH is consistent with the change of LDH activity, but it is more reflective of the activity change of LDH1, and its specificity is higher than the total LDH activity. It is more meaningful to diagnose myocardial infarction by forming myocardial zymogram with LDH, AST, CK and CK-MB. 1. The activity of α-HBDH was significantly increased in myocardial infarction, and the maintenance time was longer than that of LDH. The ratio of LDH/α-HBDH (0.8～1.2) was lower than that of normal control (1.2～1.6). 2. Identify liver disease and heart disease. LDH can be elevated in liver disease and heart disease, but the activity of α-HBDH does not change much in liver disease, the ratio of LDH/α-HBDH can be increased to 1.6-2.5, and α-HBDH is significantly increased in heart disease. 3. When malnutrition, folic acid and vitamin B12 are deficient, α-HBDH activity may also increase. High results may be diseases: precautions for myocardial infarction 1, colorimetric method: (1) The α-HBDH assay established by Rosalki and Wilkinson is a continuous monitoring method at 30 ° C, calculated in international units (U/L). The above method is a 37 ° C colorimetric method, which can be converted into the corresponding unit of the 30 ° C continuous monitoring method in order to make the results of the methods more comparable. The temperature coefficient was converted to 30 ° C at 37 ° C and the temperature coefficient was 0.87. (2) Due to the high activity of the enzyme in the red blood cells, the serum should be separated in time within 2 hours, and the specimen cannot be hemolyzed. The enzyme activity at 4 ° C was stable for not less than 7 days. (3) Anticoagulant plasma, oxalate, sodium citrate, and fluoride anticoagulant can be inhibited by EDTA (1 mg/ml) and heparin (0.2 mg/ml). 2. Continuous monitoring method: (1) This method was recommended by the British Association of Clinical Chemistry (ACB) in 1980. The optimum substrate concentration is 15mmol/L (25°C), and the final concentration of the reaction mixture: phosphate 65.4mmol/L, NADH0.2mmol/ L, α-ketobutyric acid 3.3mmol / L, sample volume fraction ratio of 0.023. The results of the change to 37 °C were better correlated with LDH. (2) Sodium α-ketobutyrate is relatively stable, α-ketobutyric acid is stored for a long time, and its condensate can inhibit the enzymatic reaction. (3) The method of domestic commodity kit is generally to mix α-ketobutyric acid and NADH solution before the operation, and after a few minutes under the reaction temperature condition, a certain amount is taken as a single reagent and added to the sample, after a delay time of 30 s, Monitor for 3 min. Inspection process 1. Colorimetric method: follow the steps. Mix well, within 10 ~ 30min, with a wavelength of 490nm, a diameter of 1cm, distilled water to zero colorimetric, with the difference of AU-AC, check the standard curve to obtain the enzyme activity unit. 2. Continuous monitoring method: (1) Take serum 0.05ml, add 2ml of NADH solution, and water bath at 37 °C for 10-15min to complete non-specific oxidation of NADH. (2) Add 0.1 ml of α-ketobutyric acid pre-warmed to 37 ° C, mix well, and immediately pour into a constant temperature cuvette at 37 ° C for monitoring. 340nm wavelength, 1cm optical path, air zero. (3) If ΔA/min>0.08, the serum is diluted 5 or 10 times with phosphate buffer and retested. Not suitable for the crowd no. Adverse reactions and risks no.