The nephron is the filter of the kidney where your blood is cleaned. Waste material is expelled as urine. The Bowman’s capsule is part of the nephron.
Bowman’s capsule is a part of the nephron which is a part of your kidney. The nephron is the filtering unit of your kidney. There are about 1 million nephrons in each kidney.
Every nephron has a glomerulus, which is a group of tiny blood vessels and the starting point for filtering waste products out of your blood. Bowman’s capsule is a two-walled pouch that covers the glomerulus. The space in between the walls of the capsule is called Bowman’s space.
Bowman’s capsule is known by other names, including the glomerular capsule, the Malpighian capsule and the renal corpuscular capsule. Bowman’s space also has other names, including glomerular capsule space, filtration space and urinary space.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Bowman’s capsule and the glomerulus make up the renal corpuscle. They are all parts of the kidney. Your kidneys have many important jobs, including controlling the pH balance of your blood, regulating blood pressure and maintaining electrolyte balance. As part of the urinary system, the kidneys are also responsible for ridding your body of waste through urine (pee).
The capsule helps the glomerulus to filter blood. Small molecules from the blood pass freely into Bowman’s space, but as long as the kidney filter is working normally, cells and large proteins stay in the blood. The small molecules then pass through tubes in the kidney, and the kidney regulates which molecules get absorbed back into your blood and which leave your body in urine.
Bowman’s capsule is located in the renal cortex, part of your kidney. The kidneys are located below your ribcage and behind your belly. Usually, there is one kidney on either side of your spine. The kidneys reside between your intestines and diaphragm. Each kidney is connected to your bladder by a tube called a ureter.
You need a microscope to see Bowman’s capsule. It resembles a pouch or sac. It’s also described as being “cup-like.”
The capsule is made up of two layers. One is the outer layer, called the parietal layer. This layer is made of body tissue known as simple squamous epithelium. The inner layer of the capsule is the visceral layer, and it’s made up of cells called podocytes. These podocytes have pedicles that look like fingers. These pedicles link together like they’re holding hands (“interdigitation”). The way they are joined creates slits that let some things go through but stops other things. When you’re healthy, protein and cell content can’t get through.
This system is the way that blood is cleaned and returned to your body, while waste materials are sent out of your body as urine through tubules (tiny tubes). The blood pressure in the glomerulus (the glomerular blood hydrostatic pressure) helps to move the blood along. As the fluids are leaving, water and nutrients are reabsorbed.
Diseases and conditions that affect your kidneys also affect Bowman’s capsule. Bowman’s capsule is especially vulnerable to diseases of the glomeruli (small blood vessels that Bowman’s capsule surrounds). There are different types of glomerular diseases. Causes range from environmental reasons to genetic ones. Glomerulonephritis refers to inflammation of the glomeruli. These conditions can be autoimmune, genetic, or infection-related diseases. Glomerulosclerosis is when the glomeruli become hard and scarred. Untreated, these diseases can result in kidney failure. Nothing causes more cases of glomerular disease and kidney failure than diabetes-related nephropathy.
Signs and symptoms of glomerular diseases may include:
Healthcare providers use several tests to measure kidney function and diagnose kidney problems. Your provider may recommend:
There’s no one-size-fits-all treatment for diseases that affect the kidneys. Your treatment will depend on what condition you have and how severe it is. Possible therapies for diseases that affect Bowman’s capsule may include:
You can help to keep Bowman’s capsule healthy by working to keep your kidneys healthy. It’s important to have regular checkups and blood and urine tests to monitor kidney health. This is especially true if you have high blood pressure, obesity and/or diabetes. You can reduce your risk of developing a kidney problem by:
If you think you might be having problems with your kidneys, you should contact your healthcare provider. You might experience signs and symptoms that include:
Your provider might suggest regular kidney function tests or blood tests if you have certain conditions, including:
A note from Cleveland Clinic
Your kidneys perform many important jobs in your body. Staying healthy by keeping blood pressure and blood glucose levels in check is key. If you think you may be having some issue with your urinary tract, whether it’s an infection or a change in your urinary habits, talk to your healthcare provider. They’ll work with you to find a solution.
Last reviewed by a Cleveland Clinic medical professional on 04/25/2022.
Learn more about our editorial process.