Lobelia chinensis
1、 Pharmacopoeia standard of Lobelia chinensis       This product is the dried whole herb of Lobelia chinensis lour., a plant of Platycodon family. Harvest in summer, remove sediment, wash and dry.
      [character] this product is often tangled. The rhizome is very short, with a diameter of 1 ～ 2mm; the surface is light brown yellow, smooth or with fine longitudinal lines The roots are small, yellow, and lateral slender fibrous roots. The stem is slender, with branches, gray green, obvious nodes, and some epiphytic fine roots can be seen. The leaves are alternate, sessile, and the leaves are mostly shrunk, green brown. After flattening, the leaves are narrow lanceolate, 1-2.5cm long and 0.2-0.5cm wide, with sparse and shallow teeth or entire edges. . The gas is slightly special, and the taste is slightly sweet and pungent.
      [identification] (1) the powder of this product is grayish green yellow or light brown yellow. The leaf epidermis cells are microwave like in the vertical wall, the stomata are indeterminate, and there are 3-7 accessory guard cells. Threaded conduits and reticulated conduits are common, with a diameter of 7-34 µ M. calcium oxalate clusters often exist beside the conduits, sometimes arranged in rows. . The parenchyma cells contain inulin, the parenchyma cells are rectangular, and the cell wall is threadlike thickened.
      (2) Take 1g of this product powder, add 50ml of methanol, sonicate for 30 minutes, cool, filter, evaporate the filtrate, add 2ml of methanol to dissolve the residue as the test solution. . According to the test of thin-layer chromatography (general rule 0502), suck 5 µ 1 each of the above two solutions, dot them on the same silica gel G thin-layer plate, use chloroform methanol (9:1) as the developing agent, develop, take out, dry, spray 10% sulfuric acid ethanol solution, heat at 105 ℃ until the spots are clear, and view them under sunlight and ultraviolet light (365nm). In the chromatogram of the test sample, spots or fluorescent spots of the same color appear at the corresponding positions of the chromatogram of the control medicinal material.
      [check] moisture   Not more than 10.0% (the second method of general rule 0832).
      [extract] according to the hot leaching method under the determination method of alcohol soluble extract (general rule 2201), the use of ethanol as solvent shall not be less than 12.0%.
      Decoction pieces
      [processing] remove impurities, wash, segment and dry.
      This product has irregular sections. The roots and rhizomes are fine, and the surface is light brown yellow or yellow. The stem is thin, gray green, and the nodes are obvious. The leaves are sessile, mostly shrunken, greenish brown, narrowly lanceolate, with sparse and shallow teeth or entire margin. It has a special smell, slightly sweet and pungent.
      [identification], [inspection], [extract] are the same as that of medicinal materials.
      [nature, taste and meridian tropism] Xin, Ping. Homing, small intestine and lung meridian.
      . It is used for carbuncle, swelling and sores, snake and insect bites, swelling and edema, damp heat jaundice, eczema and wet sores.
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      [storage] put it in a dry place.


2、 Chemical constituents of Lobelia chinensis
The whole herb contains alkaloids, mainly l-olbeline, olebelanine, lobelanidine, isolobelanine, namely nortripterine, flavonoid glycosides, saponins, litigation base acids, polysaccharides [1-3]. There are also reports of inulin, p-hydroxybenzoic acid,Fumarate(fumaric acid) andSuccinic acid（succinic acid）[4，5]。 The rhizome contains Lobeli Nin [6].

3、 Pharmacological effects of Lobelia chinensis
1. diuretic effect: anesthetized dogs IV Lobelia extract 0.1g/kg or Lobelia total alkaloids 6.6mg/kg, normal rats ig1g/kg, and normal people Po Lobelia powder 10-30g, all have significant and lasting diuretic effect, and the excretion of chloride in urine is also significantly increased. Inulin isolated from Lobelia chinensis can inhibit diuresis when given PO or IP to rats.
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3. inhibitory effect on the central nervous system: succinic acid contained in this product can protect animals against hyperbaric oxygen, electric shock and audiogenic convulsion when administered IP to mice, rats, guinea pigs, rabbits, cats and dogs. .
4. respiratory excitatory effect: Lobelia Decoction and its alkaloid preparation IV have significant respiratory excitatory effect on anesthetized dogs. Its effect was strengthened and prolonged with increasing dose. When the dose is too large, it can cause respiratory paralysis and death. After removing the sinus nerve or carotid body, and then injecting Lobelia preparation, there was no obvious respiratory excitation. It is suggested that its mechanism of action is mainly through stimulating carotid body chemoreceptors to reflexively excite the respiratory center. Lobeline had a better excitatory effect on morphine induced respiratory depression, while it had a worse effect on urethane and chloral hydrate. .
5. effect on cardiovascular system: Lobelia extract IV has significant and lasting antihypertensive effect on anesthetized dogs. For example, duodenal administration requires 10-20 times the amount of intravenous administration to have effect. It has also been reported that the decoction has a short-term pressor effect at a small dose of IV, and a longer-lasting pressor effect at a larger dose. ; At high concentrations, there is temporary excitation, followed by inhibition, and finally conduction block and asystole. Lobeline IM, while breathing excited, the heart rate slowed down and blood pressure increased; At high doses, the heart rate increases, the blood pressure decreases significantly, and finally the heart is paralyzed.
6. choleretic effect: 1g (crude drug) /kg of water boiled alcohol precipitated preparation of Lobelia chinensis in dogs IV, the bile mass flow increased by more than 2 times compared with that before administration, and the effect reached the peak after 50 minutes of administration, but the concentration of solids, cholate and bilirubin in bile decreased.
7. antivenom effect: Lobelia preparation, as well as sodium succinate, sodium fumarate and sodium p-hydroxybenzoate isolated from it, have a high protective effect on mice injected with the minimum total lethal dose of cobra venom, with a protection rate of 59.1-93.1%, 30 minutes before the injection of snake venom Po, or SC drug at the same time of the injection of snake venom, or a compound of sodium succinate, sodium fumarate and sodium acetate 30 minutes -4hpo before the injection of snake venom. However, if the drug is administered 25 minutes after the injection of snake venom, it has no protective effect.
. Lobeline can induce vomiting in cats and dogs.
8.2. laxative effect: Lobelia Decoction Po has laxative effect and can inhibit appetite.
8.3. bacteriostatic effect: in vitro test, lobelia decoction has obvious inhibitory effect on common pathogenic fungi. It also has inhibitory effect on Staphylococcus aureus and Escherichia coli.
8.4. coagulation effect: IP administration can shorten the bleeding time of mice with severed tail.
8.5. anticancer effect: lobeline at a concentration of 15mcg/ml can inhibit the oxygen uptake of mouse ascites cancer cells.