glomerulusokat

The glomerulus is a network of capillaries located within the kidney, specifically in the renal cortex, that plays a crucial role in the filtration process of blood to form urine. Each kidney contains approximately one million glomeruli, which are the fundamental functional units of the nephron—the basic structural and functional unit of the kidney. The glomerulus is encased in a cup-shaped structure called Bowman’s capsule, forming the glomerulus-Bowman’s capsule unit, also known as the renal corpuscle.

Blood enters the glomerulus through the afferent arteriole and exits via the efferent arteriole. The high pressure within the glomerulus, driven by the arterial blood supply, forces plasma—excluding large proteins and blood cells—to pass through the thin walls of the capillaries and into Bowman’s capsule. This process, known as glomerular filtration, produces an ultrafiltrate containing water, glucose, salts, and waste products. The selective permeability of the glomerular membrane allows only small molecules to pass while retaining larger components like blood cells and proteins.

The filtration barrier consists of three layers: the endothelial cells of the capillaries, a basement membrane, and the podocytes (specialized cells of Bowman’s capsule). These layers work together to regulate what substances enter the filtrate. The glomerulus is highly vascularized, receiving about 20% of the body’s cardiac output, ensuring efficient filtration.

Dysfunction of the glomerulus can lead to various kidney diseases, including glomerulonephritis, diabetic nephropathy, and nephrotic syndrome. Conditions affecting glomerular filtration can impair kidney function, leading to systemic complications such as fluid retention, hypertension, or uremia. Proper maintenance of glomerular health is essential for overall renal and systemic health.