Ma Huang

Ephedrae Herba, Ma-Huang

Dosage

The decoction is orally taken at a dose of 1.5~10g.

Toxicity

1. Ma Huang has a relatively low toxicity. Relative to pseudoephedrine, ephedrine has a higher level of toxicity, and can cause exophthalmus, tail-raising reaction and cyanose in mice. Administered to mice by abdominal injection, Mu Huang extract can cause orbital bleeding and exophthalmus. It is believed that these symptoms are caused a synergistic action of neutral substances of Ma Huang. 2. LD50 (mice/water-based extract): 78g/kg (gastrolavage); 620-650mg/kg (abdominal injection); LD50 (mice/volatile oil): 2.79 ( 0.22ml/kg (gastrolavage), 1.35ml/kg (abdominal injection); LD50 (mice/ ephedrine hydrochloride): 1.4g/kg (gastrolavage), 300-347mg/kg (abdominal injection), 1.013g/kg (hypodermic injection); LD50 (mice/pseudoephedrine): 1.55g/kg (gastrolavage), 245-269mg/kg (abdominal i

Chemical Composition

Ephedrine; Pseudoephedrine; Norephedrine; Methylephedrine; Norpseudoephedrine; Ephedroxane; (-terpineol; P-meth-2-en-7-ol; (-terpineol; Benzoic acid; P-hydroxybenzoic acid; Cinnamic acid; P-coumaric acid; Vanillic acid; Protocatechuic acid; Apigenin; Tricin; Kaempferol; Herbacetin; 3-methoxyherbacetin Kaempferol rhamnoside; Methyl-pseudoephedrine; Apigenin-5-rhamnoside,; 2, 3, 5, 6-tetramethylpyrazine ; Octadecanoic acid methyl ester ; O-benzol-L(+)-pseudoephedrine; 6, 10, 14-trimethyl-2-pentadecanone; 3, 7, 11, 15-tetramethyl-2-hexadecen-1-ol; (, (, 4-trimethyl-3-cyclohexen-1-methanol; 4', 5, 7-trihydroxy-8-methoxyflavonol-3-0-(-D-glucopyranoside. (1)

Precautions

Contraindications: spontaneous perspiration due to weak constitution, night sweat, insufficiency-type asthma, and hypertension.

Pharmacology

Effects on lipid metabolism

Research shows that Ma Huang can promote lipogenesis from glucose transformation. Ma Huang can also inhibit norepinephrine (NE)-induced lipidodieresis. This suggests that Ma Huang's effect of promoting lipidodieresis is not caused by ephedrine, and the mechanism by which it achieves this effect is similar to that of insulin. (2)

Effects on dysmnesia

Methylephedrine can significantly ameliorate scopolamine-induced memory acquirement disturbance, sodium nitrite-induced memory consolidation disturbance, and alcohol-induced memory recall disturbance in mice. (3)

Anti-coagulation effects

Experiments show that Ma Huang polysaccharides can prolong the in-vitro coagulation time, thromboplastin time and kaolin partial thromboplastin time, indicating that Ma Huang polysaccharides can affect the blood coagulation process through both intrinsic and extrinsic coagulation. (4)

Effects on blood pressure

Using the conventional carotid intubation method to record blood pressure, an experiment was set up to study the effect of Ma Huang polysaccharides on rabbits' blood pressure. Ma Huang polysaccharides were administered by IV injection at 5ml/kg on to anesthetic rabbits according to the following design: 1) group A was injected with Ma Huang polysaccharides only; 2) group B was injected with M-receptor-inhibitor atropine plus Ma Huang polysaccharides; and 3) group C was injected with a b-receptor inhibitor plus Ma Huang polysaccharides. The results: group A experienced a significant decrease in blood pressure, group A experienced no significant changes in blood pressure; and group C experienced a significant decrease in blood pressure after the injection of the b-receptor inhibitor, a decrease that continued after the injection of Ma Huang polysaccharides until the blood pressured dropped to zero. The results show that Ma Huang polysaccharides have a significant effect of reducing blood pressure, and the mechanism involves the excitation of the parasympathetic nerves. (5)

References

  1. Editorial Committee of Chinese Materia Medica. State Drug Administration of China. Chinese Materia Medica. Shanghai: Science and Technology Press; 1998.
  2. Jiang Ming, et al. China Journal of Chinese Medicine. 1999;24(5):302-304.
  3. Chang Fu Hou, et al. Journal of Inner Mongolia Medical College. 1999;21(1):28-30.
  4. Qiu Li Ying, et al. Journal of Zhangjiakou Medical College. 1999;16(1):3-4.
  5. Qiu Li Ying, et al. Journal of Zhangjiakou Medical College. 1999;16(2):1-5.