UK scientists have raised hopes of a new way to regulate blood pressure. New drugs to combat strokes and heart attacks could be on the anvil.

The body is comprised of cells consisting of molecules. Molecules are comprised of atoms containing electrons. A stable (neutral) molecule contains pairs of electrons. Where a molecule has one or more unpaired electrons, it is electrically unstable and is known as a free oxygen radical.

Energy is produced in minute structures within the cell called mitochondria. Metabolism occurs where, in an effort to balance its electrical charge, a free radical grabs an electron from another molecule. Hence, when an electron is removed from one molecule (or oxidised) and added to another (or reduced), energy is created. The energy is then stored in enzymes called ATP and is ready for release as required.

Although Free Radicals are essential to life, without adequate control, they will escape from the mitochondria and then start to attack the tissue of cell membranes and proteins in an attempt to regain their "complete" form. This can result in a chain of oxidation, damaging up to 200,000 molecules.

The results of damage to cell membranes (the damage is known as peroxidation) can be quite devastating, including an accumulation of toxic waste products in the cells, a reduction of electrical potential, a decline in vitality, an inability to repair itself effectively and a reduction in the efficiency of the immune system.

Now the pathway found in a study by King's College, PKG, London involves oxidation, reports Science.

Joseph Burgoyne and colleagues at the College have worked on Protein Kinase G (PKG), an important protein in all tissues and which plays a fundamental role in blood pressure regulation in the cardiovascular system.

They discovered that oxidants such as hydrogen peroxide cause a bond to form between two amino acids which, in turn, activates PKG. This then leads to a lowering of blood pressure.

Professor Jeremy Pearson, Associate Medical Director of the British Heart Foundation, which funded the research, said: "This research is exciting. Firstly, the team's novel discovery opens up opportunities for the design of new drugs to combat high blood pressure.

"Secondly, the mechanism provides new insights into how oxidant stress affects cells and tissues. Oxidant stress not only alters blood flow, but also affects the heart's ability to contract and is involved in a wide variety of inflammatory conditions."