1、
This product is the fresh or dry aboveground part of Leonurus Ja ponicus houtt., a Labiatae plant. ; Dry products are harvested and dried in summer when the stems and leaves are luxuriant, the flowers are not in bloom or at the beginning, or cut into sections.
[character] fresh Leonurus japonicus has no stem at seedling stage, its basal leaves are round heart-shaped, 5-9-lobed, and each lobe has 2-3 blunt teeth. The stem in the early flowering stage is square columnar, with many branches in the upper part, concave on all sides to form a longitudinal groove, 30-60cm long, 0.2-0.5cm in diameter; the surface is greenish green; The texture is fresh and tender, and the middle section is medullary. Leaves alternate opposite, stipitate; ; The lower cauline leaves are palmately 3-lobed, the upper leaves are feathery deeply or shallowly divided into 3 pieces, and the lobes are entire or with a few serrations. The breath is slight, and the taste is slightly bitter.
The stem surface of Leonurus japonicus is grayish green or yellowish green; It is light, tough, and medullary in the middle of the section. The leaves are grayish green, wrinkled, broken and easy to fall off. Cymes axillary, florets lilac, calyx tubular, corolla bilabiate. .
[identification] (1) the transverse section of the stem of this product: the epidermal cells are covered with cuticle and hairy; Glandular scales have 4, 6 or 8 cells in the head and single cells in the stalk; Non glandular hairs 1-4 cells. There were more thick horn cells in the lower cortex at the edges and corners. The cortex is a series of parenchymal cells; The endothelial layer was evident. The fiber bundles of the columella are slightly lignified. . Xylem is developed at edges and corners. The parenchymal cells in the medulla were larger. Parenchyma cells contain fine calcium oxalate needle crystals and small square crystals. The parenchymal cells of the cortex near the epidermis of the fresh product contain chloroplasts.
(2) Take 10ml of the test solution under stachydrine hydrochloride [content determination], evaporate to dryness, add 1ml of absolute ethanol to dissolve the residue, centrifuge, and take the supernatant as the test solution (the fresh product is crushed after drying, and made by the same method). . According to the test of thin-layer chromatography (general rule 0502), suck 5 ～ 10 μ l of each of the above two solutions, respectively dot them on the same silica gel G thin-layer plate, use acetone absolute ethanol hydrochloric acid (10:6:1) as the developing agent, develop, take out, dry, heat at 105 ℃ for 15 minutes, cool, spray the mixed solution of dilute bismuth potassium iodide test solution and ferric chloride test solution (10:1) until the spots are clear. In the chromatogram of the test sample, spots with the same color appear at the corresponding position of the chromatogram of the control sample.
[inspection] the moisture content of Leonurus heterophyllus should not exceed 13.0% (the second method of general rule 0832).
The total ash content of dry motherwort shall not exceed 11.0% (general rule 2302).
[extract] dry motherwort shall be determined according to the hot leaching method under the determination method of water-soluble extract (general rule 2201), and shall not be less than 15.0%.
[content determination] stachydrine hydrochloride of Leonurus japonicus was determined by HPLC (general rule 0512).
Chromatographic conditions and system suitability test propylamide bonded silica gel was used as filler; The mobile phase was acetonitrile-0.2% glacial acetic acid solution (80:20); Detected by evaporative light scattering detector. The number of theoretical plates shall not be less than 6000 according to the stachydrine peak of hydrochloric acid.
Preparation of reference solution take an appropriate amount of stachydrine hydrochloride reference, weigh accurately, add 70% ethanol to make a solution containing 0.5mg per 1ml.
Preparation of test solution take about 1g of the powder (passing through No. 3 screen), accurately weigh it, place it in a corked conical flask, precisely add 25ml of 70% ethanol, weigh it, heat it for refluxing for 2 hours, cool it, weigh it again, make up the lost weight with 70% ethanol, shake it well, filter it, and take the filtrate.
The determination method is to accurately suck 5 μ L and 10 μ l of the reference solution and 10 ～ 20 μ l of the test solution, inject them into the liquid chromatograph, determine, and calculate with the external standard two-point method logarithmic equation.
This product is calculated as dry product, and the content of stachydrine hydrochloride (c7h13no2 • HC1) shall not be less than 0.50%.
.
Chromatographic conditions and system suitability test octadecylsilane bonded silica gel was used as filler; The mobile phase was acetonitrile-0.4% sodium octanesulfonate in 0.1% phosphoric acid (24:76); The detection wavelength was 277nm. The number of theoretical plates should not be less than 6000 according to the peak of Leonurus hydrochloric acid.
Preparation of reference solution take an appropriate amount of Leonurus hydrochloric acid reference, weigh accurately, add 70% ethanol to make a solution containing 30 μ g per 1ml.
Determination method precisely suck 10 μ l of the reference solution and 10 μ l of the test solution under the item of stachydrine hydrochloride [content determination], inject them into the liquid chromatograph, and determine.
Calculated as a dry product, the content of motherwort hydrochloride (c14h21o5n3 • HC1) shall not be less than 0.050%.
Decoction pieces
[processing] fresh motherwort removes impurities and washes quickly.
Dry motherwort removes impurities, quickly wash, slightly moisten, cut into sections, and dry.
This product has irregular sections. The stem is square, concave on all sides into a longitudinal groove, grayish green or yellowish green. . The leaves are grayish green, and are often wrinkled and broken. Cymes axillary, yellow brown flowers, calyx tubular, corolla bilabiate. The breath is slight, and the taste is slightly bitter.
[extract] the same as that of medicinal materials, not less than 12.0%.
[content determination] for the same medicinal material, the content of stachydrine hydrochloride (c7h13no2 • HC1) shall not be less than 0.40%, and the content of motherwort hydrochloride (c14h21o5n3 • HC1) shall not be less than 0.040%.
[identification] (except for the transverse section of the stem) [inspection] is the same as that of medicinal materials.
[nature, taste and meridian tropism] bitter, pungent and slightly cold. Return to liver, pericardium and bladder meridian.
[functions and indications] activating blood circulation and regulating menstruation, diuresis and detumescence, clearing heat and detoxification. .
[usage and dosage] 9 ～ 30g; fresh product 12 ～ 40g.
[note] pregnant women should use it with caution.
[storage] dry motherwort is placed in a dry place; Place fresh motherwort in a cool and damp place.

2、 Chemical constituents of Leonurus japonicus

Leonurus tenuifolia containsLeonurus alkaloid、Stachydrine. Also containsL-arginine, 4-guanidino-1-butanol, 4-guanidino-butyric acidStachyose。

3、 Pharmacological effects of Leonurus japonicus

1. effect on uterus
In early years, it was proved that motherwort preparation had direct excitatory effect on isolated uterus of rabbits, guinea pigs and dogs, which was similar to pituitrin, but the effect was weak. Later pharmacological studies confirmed this theory. The water extract or ethanol extract of Leonurus heterophyllus has been proved to have excitatory effect not only in the ex vivo uterus, but also in the eutopic uterus (intravenous injection) and uterine fistula (gavage). The amplitude, contraction rate and tension of the uterus, whether pregnant or not, increase for a long time. Leonurus heterophyllus tincture seems to be less effective than decoction. Decocting for 8 hours or storing at room temperature for 2 weeks did not significantly weaken the efficacy. Its active ingredients are in the leaves, while the stems have no uterine contraction effect, and the root efficacy is also poor. The collection should be carried out when the leaves are luxuriant in May. There is also a certain component (dissolved in ether) in Leonurus japonicus that has inhibitory effect on the uterus. The Leonurus japonicus base can excite the uterus in vitro, but cannot excite the uterus in place. It has also been reported that the crude Leonurus alkaloid has no obvious effect on the isolated uterus and uterine fistula test. Leonurus alkaloids extracted by STAS Otto method have contractile effect on isolated uterus. ; It has obvious excitatory effect on isolated uterus of cat and guinea pig. There was no significant effect of orientine a extracted from seeds. The total alkaloid of Leonurus japonicus extracted from Sichuan has a contractile effect on the isolated uterus of guinea pigs, and its type of action is similar to ergonovine. The potency of 3 mg of total alkaloid of Leonurus japonicus is equivalent to 0.04 mg of ergonovine maleate. However, the effect on the eutopic uterus has not been reported. In conclusion, the water-soluble components of Leonurus japonicus have excitatory effects on the uterus of ex vivo, eutopic and overall non anesthetized animals, but its real effective alkaloids have yet to be determined.

2. effect on circulation system
The decoction of motherwort water extract, water extract or alcohol water extract, motherwort base, motherwort base a, motherwort total base and flower all have antihypertensive effect on anesthetized animals by intravenous injection, but the duration is short. Leonurus japonicus also has a certain component that causes blood pressure to rise (dissolved in ether, which has an inhibitory effect on the uterus); However, motherwort base made in the laboratory has no effect on the uterus and blood pressure of anesthetized cats, but it can reduce or even reverse the pressor effect of adrenaline. The ethanol preparation of Leonurus japonicus had mild excitatory effect on the in situ rabbit heart, and mild inhibition on the isolated rabbit heart at first, then mild excitation, and a large number of inhibition. For isolated frog hearts, Leonurus heterophylline is a small amount of excitation and a large amount of inhibition; Stachydrine can slow down the contraction rate of frog heart. . Its hypotensive effect is not affected by cutting off the vagus nerve, but can be significantly weakened by prior injection of atropine. In addition, it has anti epinephrine effect.

3. other functions
Leonurus alkaloid has been reported to excite the respiratory center. Its alkaloids can inhibit the central nervous system of frogs; Flower decoction can improve the peristalsis of large and small intestines.
Motherwort has curare like effects on neuromuscular specimens. Intravenous injection of motherwort can increase urine output in anesthetized rabbits, and high concentrations can cause hemolysis. The water extract of Leonurus japonicus (1:4) has inhibitory effect on the growth of skin fungi in vitro.