Water soluble phenolic acidsProtocatechuic acidIt widely exists in common Chinese medicines such as geranium, Salvia miltiorrhiza and classic compound preparations such as compound salvia miltiorrhiza injection and Guanxinning Injection. It can significantly reduce myocardial oxygen consumption, improve myocardial oxygen tolerance and slow down heart rate. See the following for the impact on cardiovascular system:
(1) Effect on oxygen consumption of coronary artery and myocardium
The results showed that protocatechuic acid could partially antagonize the increase of myocardial oxygen consumption induced by adrenaline. When protocatechuic acid and protocatechuic aldehyde were mixed for 10mg/kg respectively, the effect of increasing coronary sinus flow was weaker and shorter than that of the same dose of protocatechuic acid alone. However, it is superior to protocatechuic aldehyde alone in reducing arterial and venous oxygen difference and myocardial oxygen consumption. After intravenous injection of the mixture, the blood pressure first decreased briefly, then increased weakly and persistently, increased the blood flow of pancreas, portal vein and lung, and accelerated the heart rate; Reduce the blood flow of hepatic artery and renal artery.
(2) Effect on myocardial hypoxia tolerance
It is found that protocatechuic acid can significantly prolong the time of myocardial hypoxia tolerance under the condition of mild improvement of cardiac function, reduce the decrease of blood pressure caused by hypoxia and slow down the heart rate, which is beneficial to prolong the time of myocardial hypoxia tolerance. Normal pressure hypoxia tolerance test showed that protocatechuic acid could prolong the survival time of mice (maintained for more than 1.5 hours), which was similar to the effect of dipyridamole at the same dose.
(3) Effects on heart and peripheral blood vessels
After intravenous injection of protocatechuic acid, the coronary artery resistance gradually decreases, lasting for about 30min, and returns to the original level after about 1H. The mixture of protocatechuic acid and protocatechuic aldehyde shows a slow and mild pressor effect, which can dilate the blood vessels of the lower limbs of animals, but the splenic vascular response is slight, which indicates that the pressor effect has little to do with the changes of peripheral and some visceral blood vessels, so it has nothing to do with α - receptor excitation.
Protocatechuic acid can protect the cardiovascular system by reducing the oxygen consumption of coronary artery and myocardium, improving the hypoxia tolerance of myocardium, and increasing the pressure of heart and peripheral blood vessels.