Lianqiancao
1、   Pharmacopoeia standard of lianqiancao         This product is the dry aboveground part of the Labiatae plant Glechoma longituha (Nakai) kupn. .
        [character]   This product is 10 ~ 20cm long and sparsely pubescent. The stem is square columnar, thin and twisted; The surface is yellowish green or purplish red, and there are adventitious roots on the nodes; It is brittle, easy to break, and the section is often hollow. The leaves of 5 opposite leaves are mostly shrunken, kidney shaped or nearly heart-shaped after flattening, 1-3cm long and 1.5-3cm wide, grayish green or greenish brown, with round teeth on the edge; .
        [identification]   (1) Powder grayish green, non glandular hair multicellular, often one to several cells overflow, and single-cell cone-shaped non glandular hair. . Single cell of glandular hair head; Stalk single cell. The cell wall of the lower epidermis of leaves is wavy and curved. Air hole straight shaft type. The vertical wall of the upper epidermal cells is wavy and curved, with fine and dense cuticular texture. The diameter of threaded conduit and reticulated conduit is 20 ～ 3C μ M.
        (2) Take 2.5G of this product powder, add 50ml of 70% methanol, heat and reflux for 1 hour, filter, evaporate the filtrate, soak the residue with 5ml of petroleum ether (30 ～ 60 ℃) and dichloromethane respectively for 3 minutes, discard the petroleum ether and dichloromethane solution, volatilize it, add 5ml of water to dissolve the residue, elute with 80ml of water through D101 macroporous adsorption resin column (inner diameter is 1.5cm, column height is 12cm), discard the water, elute with 150ml of 35% ethanol, discard the eluent, then elute with 40ml of 70% ethanol, collect the eluent, evaporate it, add 2ml of methanol to dissolve the residue, and use it as the test solution. In addition, take 2.5G of the control medicinal material of lianqiancao and prepare the control medicinal material solution by the same method. Then take luteolin reference substance and add methanol to make a solution containing 0.1mg per 1ml as the reference substance solution. According to the test of thin-layer chromatography (general rule 0502), suck 2 ～ 6 μ l of the test solution and the reference medicinal material solution, and 2 μ l of the reference solution, respectively, onto the same silica gel G thin-layer plate, develop with cyclohexane ethyl acetate formic acid (8:9:0.5) as the developing agent, take out, dry, spray with 3% aluminum trichloride ethanol solution, heat at 105 ℃ for several minutes, and inspect under the ultraviolet light (365nm). In the chromatogram of the test sample, fluorescent spots of the same color appear at the positions corresponding to the chromatogram of the control medicinal material and the chromatogram of the control sample.
        [check]   Impurities shall not exceed 2% (general rule 2301).
        .
        The total ash content shall not exceed 13.0% (general rule 2302).
        Acid insoluble ash content shall not exceed 3.0% (general rule 2302).
        [extract]   According to the hot leaching method under the determination of alcohol soluble extract (general rule 2201), the use of dilute ethanol as solvent shall not be less than 25.0%.
        Decoction pieces
        [processing]   Remove impurities, wash, segment and dry.
        This product has irregular sections. The stem is square, and the surface is yellowish green or purplish red. The cut surface is usually hollow. The leaves are opposite, and the leaves are mostly shrunken, grayish green or greenish brown. Cymes axillary, corolla lip-shaped. It tastes fragrant and bitter.
        [identification] [inspection] (except impurities) [extract]   Same as medicinal materials.
        [nature, taste and meridian tropism]   Pungent, slightly bitter, slightly cold. It belongs to the liver, kidney and bladder channels.
        [function and indications]   . It is used for heat drenching, stone drenching, damp heat jaundice, sores, carbuncle, swelling and pain, and injury.
        [usage and dosage]   15 ～ 30g. For external use, use appropriate amount, and wash in decoction.
        [storage]   .


2、 Chemical constituents of Desmodium japonicum
The stems and leaves contain volatile oil, and the main components are pinocamphonePeppermint ketone, isophtrenone, pulegone, etc., withUrsolic acid、Succinic acid。

3、 Pharmacological effects of lianqiancao
It can clear away heat, detoxify, diuresis, remove stones, dissipate blood stasis and swelling. It is used for urolithiasis, hepatolithiasis, damp heat jaundice, and traumatic injury.