What are the effects and functions of Apocynum venetum? A comprehensive guide

Apocynum venetum, also known as red hemp, tea flower, red willow seed and so on, is an erect subshrub of the genus Apocynum in the dogbane family (Apocynaceae). It is distributed in all provinces (autonomous regions) north of the Huai River, Qinling Mountains and Kunlun Mountains in China. It has the effects of clearing fire, lowering blood pressure, strengthening the heart and promoting urination, and has therapeutic effects on heart disease, hypertension, kidney deficiency and so on. Let us take a look at the effects and functions of Apocynum venetum together below!

Medicinal effects of Apocynum venetum

[Nature and flavor] Sweet and bitter in taste, cool in nature, slightly toxic.

[Meridian tropism] Liver meridian.

[Effects] Calms the liver and soothes the nerves, clears heat and promotes urination. Used for dizziness due to liver yang, palpitations and insomnia, edema with scanty urine, hypertension, neurasthenia, and edema due to nephritis.

Medicinal supplementary formulas of Apocynum venetum

1. To treat hepatitis with abdominal distension: Apocynum venetum 2 qian, muskmelon pedicel 1.5 qian, Corydalis yanhusuo 2 qian, clove 1 qian, costus root 3 qian. Grind together into powder, take 5 fen at a time, twice a day, taken with boiled water.

2. To treat neurasthenia, dizziness, sequelae of cerebral concussion, palpitations, insomnia, hypertension, ascites due to cirrhosis, and edema: Apocynum venetum 1 to 3 qian. Brew with boiled water and drink as tea; do not decoct.

Pharmacological effects of Apocynum venetum

1. Blood pressure-lowering effect: After gavage of Apocynum venetum leaf decoction to dogs with renal hypertension, 2 hours later the blood pressure dropped from 194/142 mmHg to 152/100 mmHg and remained stable at a lower level, only rising again after 3 days.

2. Cardiac-strengthening effect: The cymarin contained in Apocynum venetum root can increase the contraction amplitude of isolated and in situ cat hearts, slow the heart rate, then cause arrhythmia, and finally cardiac arrest in systole. Its action properties and speed are similar to strophanthin, and central depressants such as sodium pentobarbital can weaken its cardiac-strengthening effect. Experiments with Apocynum venetum root extract on in situ cat hearts also showed cardiac glycoside-like effects.

3. Effects on experimental heart disease: Cymarin has a therapeutic effect on experimental cardiovascular insufficiency in dogs, alleviates the symptoms of acute circulatory disturbance in rabbit myocarditis, and can prevent myocardial and coronary vascular sclerosis; this effect is superior to that of strophanthin. It can restore the electrocardiographic changes of atherosclerotic rabbits to normal, and its contractile effect on the coronary arteries is particularly significant. It also has a therapeutic effect, though weaker, on atherosclerotic rabbits with insufficient coronary circulation function caused by pituitrin and thrombin. It can increase cardiac glycogen resynthesis. This indicates that Apocynum venetum leaf has a lowering effect on elevated endogenous blood lipids.

4. Anti-radiation damage: Apocynum venetum leaf extract 2 g/kg by gavage, 0.5 g/kg by intraperitoneal injection, for 15 to 20 consecutive days, can prolong the survival days of mice irradiated with 60Co γ-rays, increase the survival rate, and increase the blood white blood cell count. Quercetin 30 mg/kg by gavage also has the same effect. It is believed that the anti-radiation effect of Apocynum venetum leaf is related to quercetin.

5. Effects on the spleen: Triacontanol has no obvious effect on the growth of normal young mice, has a weight-increasing effect on the spleen of mice, especially significant with intramuscular injection of 20 mg/kg, and has inconsistent effects on the mouse thymus: the thymus of adult mice slightly increases in weight, while that of young mice slightly decreases. It has a clear antagonistic effect on spleen and thymus weight loss caused by cyclophosphamide, and enhances the phagocytic function of mouse peritoneal macrophages.

6. Effects on the cardiovascular system: Apocynum venetum extract aqueous filtrate (10%) was injected intravenously at a constant rate into anesthetized dogs (2.0 mL/kg, 3.6 mL/min); blood pressure decreased, with a maximum decrease of 22.3%. The decrease in blood pressure was accompanied by a slowing of heart rate, and the slowing of heart rate lasted for 30 minutes after administration. Along with the decrease in blood pressure, cardiac output, cardiac index, stroke index and blood flow in the left circumflex branch of the coronary artery decreased. There was no effect on cardiac preload and afterload. Myocardial oxygen consumption decreased within 3 minutes of intravenous injection.

7. Diuretic effect: Apocynum venetum leaf aqueous extract and the incinerated residue of the extract have a diuretic effect. After oral administration of Apocynum venetum leaf aqueous extract to rats, the total urine volume increased by 50.60% and 32.28% at 6 to 24 hours and 24 hours respectively. At the same time, urinary sodium and urinary potassium excretion also increased correspondingly, but there was no significant difference in urinary potassium and urinary sodium concentrations between the administration group and the control group.

8. Blood lipid-lowering effect: Apocynum venetum leaf aqueous extract can significantly reduce the serum total cholesterol value and triglyceride value of rats with Triton-induced hyperlipidemia, but it failed to reduce the cholesterol value of mice with hypercholesterolemia formed by a high-fat diet.

9. Anti-aging effect: Apocynum venetum leaf extract has an anti-aging or life-prolonging effect on fruit flies, silkworms and mice. Apocynum venetum leaf extract reduces the lipofuscin content in the internal organs of mice to varying degrees, and can generally increase the superoxide dismutase (SOD) activity in the liver and heart of mice of different age groups. Apocynum venetum tea can increase the SOD value and HDL-e in red blood cells, and may be beneficial for preventing arteriosclerosis.

10. Other effects: Intraperitoneal injection of Apocynum venetum leaf extract 0.5 g/kg into mice reduced spontaneous activity significantly after 30 minutes, and the effect lasted for more than 5 hours. It also has a synergistic effect on the sedative and hypnotic action of pentobarbital, and has a certain anticonvulsant effect. When the Apocynum venetum leaf decoction was at a concentration of 1:1000, it had no obvious effect on the contraction amplitude and frequency of isolated rat uterine smooth muscle; at 1:2000, it significantly reduced the contraction of isolated rabbit intestinal muscle and rat uterus and slowed the frequency.