1. interference with arterial response to catecholamines,

2. reduction of norepinephrine efflux from perivascular nerves,

3. decrease of noradrenergic activity,

4. suppression of prostaglandin production,

5. influence on nitric oxide production,

6. via specific receptors.

Additionally, melatonin may reduce blood pressure via the following mechanisms:

1. by a direct effect on the hypothalamus;

2. as an antioxidant which lowers blood pressure;

3. by decreasing the levels of catecholamines, or

4. by relaxing the smooth muscles, lining the aorta.

Concluding, as melatonin concentrations have been reported to decrease with age and in many cardiological diseases, melatonin replacement therapy may decrease the incidence of sudden cardiac death during acute myocardial infarction disease and hypertension especially in elderly patients.

Studies have demonstrated that melatonin has significant effects on ischemia-reperfusion injury, myocardial chronic intermittent hypoxia injury, pulmonary hypertension, hypertension, valvular heart diseases, vascular diseases, and lipid metabolism

Please go through the following RG links.

Article Effects of melatonin on cardiovascular diseases: progress in...

Article Melatonin and age‐related cardiovascular diseases

Article Melatonin and Human Cardiovascular Disease

Article Melatonin in Heart Failure: A Promising Therapeutic Strategy?