Dong quai oil helps blood circulation, relieving pain, laxative function, and has high medicinal and health value. The study found that dong quai contains flavonoids, coumarin, essential oil, organic acids, polysaccharides, amino acids, trace elements and vitamins and other ingredients. Dong quai is rich in chemical compositions although essential oil accounts for only 0.62% of the total composition of dong quai. The extensive pharmacological effects have been widely used clinically. At present, there are over 40 national drug preparations containing dong quai oil.

Health Benefits

Impact on the uterus
Uterine smooth muscle
The normal rat uterine smooth muscle contractile regulation from dong quai oil is two-way, mainly small dose (≤20mg/L) excited, high-dose (≥160 mg/L)inhibition; the part with the best uterine contraction inhibition dong quai is the neutral, non-phenolic composition of oil. A larger dose of dong quai oil inhibits the oxytocin-induced uterine smooth muscle excitability, and significantly inhibits the high potassium depolarizing solution Ca2 + caused uterine smooth muscle contraction.

The reaction of the uterine muscle strips under oxytocin and high potassium depolarization solution is also observed, the result shows that dong quai oil significantly inhibits intracellular and extracellular Ca2 + induced uterine smooth muscle contraction, suggesting that dong quai oil may be related to the inhibition of uterine smooth muscle strips in vitro antagonistic Ca2 +-related.

Dysmenorrhea treatment
During the experiments of normal and oxytocin hormone-treated mice isolated uterine smooth muscles, the impact of dong quai oil on the contraction amplitude, contraction frequency and activity of the two uterine smooth muscles shows, dong quai oil can inhibit the isolated uterine smooth muscle contraction, mainly as tension drop, slow rhythm and contraction decreasing, which can be used for dysmenorrheal treatment.

During another experiment, the dysmenorrhea model mice was measured uterine weight, uterine tissue nitric oxide (NO) and Ca2 + levels, after research on dong quai oil on the uterus. The results showed that dong quai oil can reduce the oxytocin-induced dysmenorrhea mouse writhing (P <0.01), dysmenorrhea model mice uterine weight had no significant effect (P> 0.05). Uterine tissues of mice given the oil of dong quai NO were significantly increased (P <0.05), and Ca2 + was significantly lower (P <0.01). dong quai oil inhibits oxytocin-induced dysmenorrhea writhing and increases NO level significantly, while reducing the level of calcium. These effects may be part of the mechanism of dong quai oil on the treatment of primary dysmenorrhea.

Impact on bronchial smooth muscle
Ligustilide from dong quai oil owns strong antispasmodic asthma function, which has the relaxation of bronchial smooth muscle against histamine, acetylcholine-induced bronchial asthma, and the anti-asthmatic effect ligustilide 0.14 mg/kg is similar with aminophylline 50mg/kg. Ligustilide not only relaxes the guinea pig body organs apparently, also has significant antispasmodic effect on acetylcholine, histamine,and barium chloride-induced organ smooth muscle spasm.

Impact on the immune system
The impact of total dong quai lactone(based ligustilide of dong quai oil) in vitro experimental observations impact on the function of mice immune cells shows that dong quai total lactones can significantly promote the spleen cells, thymuscell proliferation, and the total dong quai lactones of different concentrations can enhance interleukin -2 (IL-2)-induced LAK cell killing activity, significantly enhance the ability of the cells to produce IL-2 of the mouse spleen and cyclophosphamide (100 mg/ kg) in mice caused by immune function inhibition, while restoring the mouse spleen. dong quai lactones can significantly increase the mouse L3T4 + and Lyt2 + cell ratio, at a concentration of 250 μg/ml, dong quai total lactones significantly enhance the functionality of the mouse cytotoxic T lymphocytes (CTL), increased its cytotoxic activity by 80%.

Impact on the cardiovascular system
Impact on myocardial physiological properties and action potential
The neutral and non-phenolic part of dong quai oil can slow down heart rate, and has antiarrhythmic role. We adopt the conventional isolated organ experiments to record the stroke frequency of the right atrium of the SD rats, myocardial contractility and functional refractory period, and apply microelectrode technique within standard cells to record the action potential.

The results show that, the neutral, non-phenolic part of dong quai oil(10-160 mg/l) can significantly inhibit the self stroke frequency of right atrium, 160 mg/l can make the right atrium arrest, which may be its block Ca2 + and if stream or promotion of K+ efflux related; it reduces the contraction force of the left atrium, IC50 is 52.3 mg/l; it significantly extends the functional refractory period (FRP), 100 mg/l, the FRP was extended to 130 ms from 106 ms before the administration, which may be related block Na + influx; reducing action potential amplitude (APA), shortening 20% repolarization(APD20) and 90% repolarization time(APD90,), had no effect on the resting potential (RP), which may be related to block Ca2+ influx and promote K+ efflux related to the maintenance of the RP inward rectifier potassium current, which may be related to the selective K+ channel function.

Protection for focal cerebral ischemia
We make rat cerebral artery occlusion (MCAO) model with structure method to simulate the pathological process of clinical ischemic cerebrovascular disease, with TTC staining to evaluate the infarct area of brain tissue, immunohistochemistry to detect induciblenitric oxide synthase (iNOS) expression in brain tissue, spectrophotometric method to determine iNOS activity and NO content in the brain tissue.

Experimental results show that dong quai lactone significantly reduces the infarct area of MCAO-induced rat (P<0.01), and greatly improves the MCAO rats neurological symptoms (P<0.01), and reduces the amount of iNOS expression in the ischemic brain tissue, enzyme activity and NO levels.

Impact on coagulation system
We observed the impact of dong quai oil on ADP-induced platelet aggregation and prothrombin time, the result shows dong quai oil has anti-platelet aggregation role and prolong prothrombin time.

Inflammatory and analgesic effects
The acute inflammation model (xylene-induced mouse ear edema, acetic acid-induced mouse peritoneal capillary permeability, egg white-induced paw edema) and sub-acute inflammation model (rat granuloma in hyperplasia) are applied to observe the impact of dong quai oil on experimental acute and chronic inflammation, swelling and hyperplasia; chemical irritants (acetic acid) is injected into mouse peritoneal, which caused a large area, deep and long-lasting pain animal model, which is used to observe the pain inhibition of dong quai oil.

Experimental results show that dong quai oil can inhibit the edema and exudation of early inflammation, it can suppress the tissue and formation of granulation tissue of inflammatory, also has a certain inhibition role on writhing reaction in mice caused by the chemical substance (acetic acid), and some anti-inflammatory and analgesic effects.

Conclusion

Dong quai is a common traditional Chinese medicine, dong quai oil contains ligustilide,6-n-butyl cycloheptadiene, 1-methyl-1-indanol oxide, caryophyllene, palmitic acid, o-phthalicformic acid and carvacrol chemical composition. Dong quai oil has two-way adjustment for normal rat uterine smooth muscle contractile function, which is used to treat dysmenorrheal, protect focal cerebral ischemia and improve myocardial ischemia, antiarrhythmic, antiasthmatic, improve immunity and anti-inflammatory and analgesic.It is believed Dong quai oil more chemical components will be separated from dong quai oil with the progress of modern separation technology, we will have more development on dong quai oil.