CorpusHuman Anatomy
UrinaryOrgan part

Glomerular capsule

Capsula glomeruli

Also known as: Bowman's capsule, Bowman capsule, Bowman's space, capsular space

The double-walled epithelial cup at the start of the nephron that encloses the glomerulus and collects the filtrate in the capsular (Bowman) space before it flows into the PCT.

Show on body map Nephron — Juxtamedullary

Overview

During development the blind end of the nephron is invaginated by the glomerular capillaries, producing a double layer. The visceral layer is made of podocytes that wrap the capillaries and form the outer part of the filtration barrier. The parietal layer is a simple squamous epithelium on a basement membrane that forms the outer wall and is continuous with the PCT at the urinary pole. Between them, the capsular (Bowman) space receives the ultrafiltrate; its hydrostatic pressure (≈15 mmHg) opposes filtration and its oncotic pressure is normally ≈0.

In severe glomerular injury, parietal epithelial cells and macrophages proliferate in the capsular space to form crescents — the hallmark of rapidly progressive glomerulonephritis.

Location

Renal cortex, surrounding each glomerulus.

Parts & subdivisions

  1. Visceral layer
    Podocytes with interdigitating foot processes and slit diaphragms.
  2. Parietal layer
    Simple squamous epithelium forming the outer wall.
  3. Capsular (Bowman) space
    Receives filtrate; continuous with the lumen of the PCT.

Anatomy

Histology

Parietal: simple squamous epithelium; visceral: podocytes. Abrupt transition to the cuboidal brush-bordered PCT at the urinary pole.

Function

  • Collect glomerular filtrate and direct it into the PCT
  • Visceral layer contributes to filtration selectivity
Physiology

Bowman space hydrostatic pressure ≈15 mmHg — rises with ureteric or tubular obstruction, reducing GFR.

Clinical significance

Crescentic (rapidly progressive) glomerulonephritis

Crescents of proliferating parietal cells, macrophages and fibrin fill Bowman space; kidney function is lost over days to weeks. Causes: anti-GBM disease, ANCA vasculitis, severe immune-complex GN. Requires urgent immunosuppression ± plasma exchange.

Compiled from standard anatomy and physiology references — see the Urinary System sources. For education only; not medical advice.