Nitric oxide and oxidant stress in hypertension [ 2003 - 2005 ]

Research Grant

Researchers: Prof Stephen Duffy (Principal investigator)

Brief description According to current National Heart Foundation surveys high blood pressure affects almost 3 million Australians, and accounts for about 6% of the total burden of disease. Unless effectively treated, high blood pressure may result in serious complications such as stroke, heart attacks and heart failure. Despite the fact that there are now many effective blood pressure-lowering medications available, blood pressure control in the community is often poor. The cause of high blood pressure in most people is unknown, but there is consistent information from population studies that low vitamin C intake is associated with high blood pressure. Recently, it has been shown that a diet rich in fruit and vegetables can lower blood pressure. We recently demonstrated in a small study that vitamin C tablets for one month lowered blood pressure, suggesting that vitamin C was the key beneficial element of the fruit and vegetable diet. Interestingly, some recent work suggests that the recommended daily allowances of vitamin C are less than a third of what they need to be to get effective levels of vitamin C in body tissues. Studies in animal models of high blood pressure have shown that oxidant levels are increased. This can affect the ability of blood vessels to relax, and may be a cause, rather than a result of high blood pressure. It seems possible that vitamin C (a strong antioxidant) may be having its beneficial effect by reducing 'oxidant stress' in blood and blood vessel walls. The purpose of this project is to further determine the effect of oxidants and antioxidants (specifically vitamin C) on blood pressure and blood vessel function in patients with high blood pressure. It is clearly prudent to eat a diet rich in fruit and vegetables, but it is important that we understand why this is so, and whether specific dietary components are critical. Vitamin C might potentially make a major impact on the presence and severity of high blood pressure in the Australian community.

Funding Amount $AUD 249,750.00

Funding Scheme NHMRC Project Grants

Notes New Investigator Grant