Studies have shown the main hypotensive constituent of the herb is pinoresinol diglucoside. The herb has a direct dilatory action on the vascular musculature. The hypotensive effect is thought to result as a consequence of central inhibition.

The herb has direct action on the blood vessels, at low dosage producing dilatation of the coronary and renal blood vessels and at a higher dosage causing vasoconstriction.

The ethanol extract of the herb increases heart rate and contraction amplitude. The herb exhibits a marked cardiotonic action.

E. ulmoides markedly reduces serum cholesterol.

The herb elicits a marked decrease of the blood's eosinophilic leukocytes. One of the antiinflammatory mechanisms involves enhancement of the adrenocortical function.

The alcohol extract antagonizes the stimulant action of pituitrin and acetylcholine, restoring the normal state of the organs.

Daily intragastric administration of the decoction to mice at the dose of 6g/kg for 5 days enhanced the phagocytosis of carbon. The carbon clearance of the decoction was about the same as that of intragastric administration of 3g/kg of the roots of Astragalus membranaceus and of Codonopsis pilosula. Intragastric administration of E. ulmoides decoction at 12g/kg significantly increased the phagocytosis of erythrocytes by macrophages compared with that in animals given the roots of Astragalus membranaceus and of Codonopsis pilosula. These results proved that the herb potentiated the immunologic functions of the body onload="highlight();" .

The various preparations of the herb exhibited diuretic action in anesthetized dogs; the diuretic action was also shown in dogs that had developed an acute tolerance to the hypotensive action of the herb.

In vitro, the herb decoction exhibited various degrees of inhibition against Staphylococcus aureus, Shigella flexneri, Escherichia coli, Pseudomons aeruginosa, Bacillus anthracis, Corynerbacterium diptheriae, Diplococcus pneumoniae and beta hemolytic Streptococci.

Large doses (20-25g/KG per day) of E. Ulmoides have an inhibitory effect on the central nervous system of dogs and mice.

Two hundred and fifty one cases of hypertension, of which 57 belonged to stage I, 173 stage II and 21 stage III were treated with the tablet of the bark of E. ulmoides at the dose of 5 tablets each containing 50mg of crude drug, three times daily for 30 days. Marked effects were achieved in 125 cases and improvement in 80 cases; the aggregate effective rate of reduction in the diastolic pressure was over 80%.

The most obvious action of the herb was in the relief of hypertensive symptoms. After one week of treatment most patients experienced a stable emotional state, and felt mentally refreshed and relaxed. Marked amelioration of headache, dizziness, palpitation and insomnia were achieved.

Oral administration of the bark of E. ulmoides as tea or wine to 62 hypertensive patients resulted in improvement after 2-4 months in 94% of cases. The systemic arterial hypotension caused by the extract of E. ulmoides is apparently the result of peripheral vasodilation by direct action on the vascular smooth muscle.

121 cases of various types of arthritis and lumbago were treated with intramuscular injection of E. ulmoides leaf preparation (0.3 g/ml) at the dose of 2-4ml once or twice daily; the treatment course lasted 3-4 months on average, the shortest being 1 month. It was effective in 87.4%; 42.1% had marked effects.

Oral administration of extract of the bark of E.ulmoides increased the plasma levels of cAMP and cGMP from 70.9 and 54.5 pml/ml in the control group to 100.4 and 137.8 pml/ml, respectively.

Except those noted, all references come from Weng Weiliang, et al., Clinical Chinese materia medica, Henan Science & Technology Press, 1998