Renal

This is a medical term used to describe the kidneys and how they work.

See our information on kidney disease

Back to top

Renal angiogram

This is a type of X-ray that is used to look at the size and shape of the blood vessels that supply the kidneys, and to see whether they are working properly or not.

Back to top

Renal artery stenosis

Renal artery stenosis is a condition that can raise blood pressure. It occurs when one or both of the blood vessels that supply the kidneys becomes narrowed. The flow of blood to the kidneys is slowed and the kidneys try to restore the flow speed by producing more renin, a hormone that raises blood pressure.

See our information on kidney disease

Back to top

Renin

This is a hormone that is produced by the kidneys and raises blood pressure. Renin makes the body produce a hormone called angiotensin, which causes blood vessels to become more narrow.

Back to top

Renin-angiotensin system

This is a powerful hormone system that helps to control your blood pressure. The hormones renin and angiotensin make the blood vessels become more narrow, raising your blood pressure. Many of the medicines used to treat blood pressure act on this hormone system.

Back to top

Retinopathy

Retinopathy is a problem with the inside of the eye that may cause some loss of sight. It may be caused by high blood pressure damaging the small blood vessels that supply the retina of the eye.

See our information on eye tests

Back to top

Sclerosis

Sclerosis is the hardening of the blood vessels. This can raise your blood pressure because your blood vessels are not as flexible as they used to be and can’t open up as much.

See our information on your arteries and high blood pressure

Back to top

Secondary hypertension

This is a form of high blood pressure that is due to an identifiable cause – for example kidney disease or a problem with the adrenal glands. Treating the original medical problem may lower the blood pressure back to normal levels.

Back to top

Sodium

The part of salt that raises blood pressure.

See our information on salt

Back to top

Sphygmomanometer

A sphygmomanometer is a device used to measure blood pressure. A cuff is placed around your arm or wrist and inflated until your blood supply is stopped. Air is slowly let out of the cuff and the device measures when the blood flow starts again (your systolic or top pressure), and when the flow is completely normal (your diastolic or bottom pressure).

Back to top

Statin

This is a type of medicine that is used to lower cholesterol levels in the blood.

See our information on fats and cholesterol

Back to top

Stenosis

Stenosis is also known as a stricture. It is used to describe an unwanted narrowing of a blood vessel.

See our information on your arteries and high blood pressure

Back to top

Stroke

A stroke occurs when a blood vessel supplying part of the brain ruptures or becomes blocked. When this happens, the brain cells in that area of the brain no longer get the energy and oxygen they need and die. The result is that the functions that the dead brain cells controlled (for example speech, memory or movement of a specific part of the body) can be damaged or lost.

See our information on stroke

Back to top

Sympathetic nervous system

A system which helps control your blood pressure by telling the body to release the hormones adrenaline and noradrenaline. These hormones can cause the blood vessels to become narrower, which raises blood pressure.

Back to top

Systolic

When your blood pressure is measured it will be written as two numbers, e.g. 120 over 80 (120/80). The first number is your systolic reading. It is the highest level your blood pressure reaches when your heart beats and pushes the blood round your body.

See our information on what is blood pressure?

Back to top