Yew

Yew

(records of medicinal plants in Northeast China)

[synonym] Chibaisong (Sheng Jing Tong Zhi), zibaisong (Meng Wen Hui Shu).

[source] it is the branch and leaf of Taxus cuspidata.

[plant morphology] Taxus cuspidata

Evergreen trees, up to 20 m high. The bark is reddish brown, lobed, with dense branches and alternate twigs. Stipe 2-5-mm wide, apex glaucous, 2-2.5-fold longer than basal vein, apex glaucous, 2-5-fold longer than basal vein. The male flower has 9-15 stamens and 5-6 anthers, and the female flower has ovoid pale red ovules. The seed is ovoid, born in the red fleshy cup-shaped or jar shaped aril, purple brown when ripe, shiny, about 6 mm long, with 3-4 blunt longitudinal ridges at the upper part, a small convex tip at the top, hilum usually triangular or sub square, sparse wide elliptic; there are several pairs of scales at the base of the aril. The flowering period is from March to June. The fruiting period is September.

Scattered in mountain forest. Distributed in Liaoning, Jilin, Heilongjiang and other places.

[chemical constituents] the leaves contain diterpenoids: taxane, taxane a, taxane h, and L. in addition, they contain ponosterone a, ecdysterone, and genistein. The tender shoots contain paclitaxel. The stem bark contains taxol with anti leukemia and anti-tumor effects. The heartwood contains paclitaxel.

(1) hypoglycemic effect

Paclitaxel has no significant effect on normal rabbits by subcutaneous or intravenous injection, but it has hypoglycemic effect on hyperglycemia (adrenaline or food) by subcutaneous or intravenous injection of 1-5 mg / kg.

② Other functions

0.1% paclitaxel can anesthetize Paramecium, paralyze the central nervous system of frogs, mice and rabbits, and the minimum lethal dose to rabbits is 4.5 mg / kg. A small amount of it can excite the isolated rabbit intestines, but more than 0.002% of it can inhibit it. It has paralytic effect on the uterus of non pregnant mice and rabbits in vitro (0.01%), but it has excitatory effect on pregnant uterus. It can inhibit the blood vessels of isolated frog heart, toad legs or rabbit ears, and reduce the blood pressure of rabbits. Long term subcutaneous injection (5-10 mg / kg) had no significant effect on the excretion of urinary total nitrogen and sulfate. The lethal dose of paclitaxel is 2-3 mg / kg. Paclitaxel is a mixed alkaloid. Paclitaxel a (from Taxus aureus) has little toxicity. It has no obvious effect on rats by intravenous injection of 5 mg / kg or guinea pigs by intravenous drip of 62 mg / kg / h. The median lethal dose of paclitaxel B was 4.5 mg / kg in rats, 0.9 mg / kg in cats and 0.53 mg / kg in electrocardiograms. Paclitaxel could slightly inhibit the respiration of ascites cancer cells (the effective concentration was 80 μ g / ml).

Functions and indications: materia medica tuichen: "diuresis, menstruation. Kidney disease, diabetes. "

[usage and dosage] oral administration: decoction, leaf: 1-2 Qian; twig (peeled): 3-5 Qian.

[selection] ① diabetes: Yeerqian. Decoction, twice a day, continuous use (if nausea and vomiting side effects, then stop; no side effects, can gradually add to 5 money up). (Jilin Chinese herbal medicine)

② Treatment of nephritis edema, urine adverse: Taxus leaf two money, Mutong three money, corn must three money. Fried in water, twice a day. (Jilin Chinese herbal medicine)