Hawthorn leaf
1、 Pharmacopoeia standard of Hawthorn Leaves This product is the dried leaves of Rosaceae plant Crataegus pinnatifida bge.var.major n.e.br. or hawthorn grataegus pinnatifida bge. Harvest in summer and autumn and air dry. ; The petiole is 2 ～ 6cm long, and the stipules are oval to ovate lanceolate The breath is slight, and the taste is astringent and bitter. [identification] (1) the powder of this product is green to brownish yellow. The diameter of calcium oxalate cluster crystals is 10 ～ 30 μ m, and the diameter of calcium oxalate square crystals is 15 ～ 30 μ m, which are scattered or distributed near the vascular bundles or fiber bundles of leaves. The conduit is a threaded conduit with a diameter of 20 ～ 40 μ M. The non glandular hairs are unicellular, oblong and conical, with a base diameter of 30-40 μ M. The fibers were in bundles, with a diameter of about 15 μ m, and the wall was thickened. (2) . In addition, take rutin reference substance and Hyperoside reference substance, add ethanol to make a solution containing 0.1mg per 1ml as the reference substance solution, test according to thin-layer chromatography (general rule 0502), suck 1 ～ 2 μ l of each of the three solutions, dot them on the same polyamide film, use ethanol acetone water (7:5:6) as the developing agent, develop, take out, air dry, spray aluminum trichloride test solution, dry with hot air, and view under ultraviolet light (365nm). In the chromatogram of the test sample, fluorescent spots of the same color appear at the corresponding positions of the chromatogram of the control sample. [inspection] the moisture content shall not exceed 12.0% (the second method of general rule 0832). The insoluble ash content of brewing shall not exceed 3.0% (general rule 2302). [extract] according to the cold leaching method under the determination method of alcohol soluble extract (general rule 2201), using dilute ethanol as solvent, it shall not be less than 20.0%. . Accurately measure 20ml, put it into a 50ml measuring bottle, add water to the scale, shake well, and get (each 1ml contains 0.2mg of anhydrous rutin). Preparation of standard curve accurately measure 1ml, 2ml, 3ml, 4ml, 5ml, 6ml of the reference solution, place them in 25ml measuring flasks, add water to 6ml each, add 1ml of 5% sodium nitrite solution, shake well, place for 6 minutes, add 1ml of 10% aluminum nitrate solution, shake well, place for 6 minutes, add 10ml of sodium hydroxide test solution, add water to the scale, shake well, place for 15 minutes, take the corresponding reagent as blank, immediately according to the UV visible spectrophotometry (general rule 0401), measure the absorbance at the wavelength of 500mn, and draw the standard curve with absorbance as the ordinate and concentration as the abscissa. Determination method take about LG of the product's fine powder, accurately weigh it, put it in Soxhlet extractor, add chloroform to heat and reflux to extract until the extraction solution is colorless, discard the chloroform solution, volatilize the chloroform from the drug residue, add methanol to continue extracting until colorless (about 4 hours), evaporate the extraction solution, add dilute ethanol to dissolve the residue, transfer it to a 50ml volumetric flask, add dilute ethanol to the scale, shake well, and use it as the test article storage solution. . This product is calculated as a dry product, and the total flavonoids contained shall not be less than 7.0% based on anhydrous rutin (c27h30o16). Hyperoside was determined by HPLC (general rule 0512). Chromatographic conditions and system suitability test octadecylsilane bonded silica gel was used as filler; The mobile phase was acetonitrile methanol tetrahydrofuran-0.5% acetic acid solution (1:1:19.4:78.6); The detection wavelength was 363nm. The number of theoretical plates should not be less than 3000 according to hyperin peak. Preparation of reference solution take a proper amount of hyperin reference, weigh accurately, and add dilute ethanol to make a solution containing 20 μ g per 1ml. Preparation of test sample solution take the test sample stock solution under the item of total flavonoids [content determination], filter it, and take the secondary filtrate. . The content of Hyperoside (c21h20o12) in this product shall not be less than 0.050% calculated as a dry product. [nature, taste and meridian tropism] sour, flat. Return to liver meridian. . It is used for qi stagnation and blood stasis, chest pain, chest tightness and suffocation, palpitations and forgetfulness, dizziness and tinnitus, and hyperlipidemia. [usage and dosage] 3 ～ 10g; or make tea. [storage] put it in a dry place.

2、 Chemical constituents of Hawthorn Leaves
Mountain red leaves containquercetin (quercetin)，Hyperin(hyperoside)，Vitexin(vitexin)，Vitexin rhamnoside(rhamnosylvitexin)， 2-p-hydroxyphenylmethylmalic acid [2- (4-hydroxybenzyl) malicacid], diethylamine hydrochloride, sorbitol.

3、
1. effects on the cardiovascular and cerebrovascular systems. Hawthorn leaf polymerized flavone can antagonize pituitrin induced acute myocardial ischemia in rabbits and reduce the scope of myocardial infarction after one or more administrations. Hawthorn leaf extract (0.1g/ml) 0.4-8ml/kg intravenously can significantly reduce or restore the S.T segment up shift and T wave increase of guinea pig ECG caused by pituitrin, and accelerate the heart rate slowing caused by pituitrin. Vitexin rhamnose II 20ml/kg can significantly reduce the myocardial oxygen consumption of canine eutopic heart, and has a synergistic effect with hyperin. Gavage of hawthorn leaf water extract to rats can significantly reduce the serum phosphocreatine kinase (CPK) level and myocardial infarction size in rats with ligated coronary artery. When 20% hawthorn extract was injected into jugular vein for 5-7min, cerebrovascular resistance decreased by 1.064-10.91kp/a (8-82mmhg).

2. effect on coagulation system. Hawthorn leaves can significantly inhibit collagen or ADP induced platelet aggregation in rabbits both in vivo and in vitro. In addition, 30min after intravenous injection of hawthorn leaf preparation, the whole blood specific viscosity decreased significantly.

3. hypolipidemic effect. .

4. hypoxia resistance. Hawthorn leaves, like propranolol, can significantly prolong the survival time of low-pressure hypoxia or normobaric hypoxia experimental mice, consistent with the effect of significantly reducing the overall oxygen consumption of mice.

5. diuretic effect. Hawthorn leaf extract has obvious diuretic effect. The urine volume of rabbits increased by 44.2% after 60min, 53.9% after 90min, and 63.7% after 120min compared with that before administration, indicating that its diuretic effect is mild, slow, and lasting, and hawthorn leaf diuresis has little effect on electrolyte.