Histology of Kidney and Bladder Lab

Nephron Structure

The nephron, the kidney's functional unit, comprises two main regions:

• Renal Corpuscle: Includes the glomerulus (a capillary ball) and the glomerular capsule (Bowman's capsule).
• Renal Tubule: Consists of the proximal convoluted tubule, nephron loop (Loop of Henle), and distal convoluted tubule, which empties into the collecting duct.

Kidney Regions: Cortex and Medulla

• Cortex: Contains glomeruli with glomerular capsules and proximal and distal convoluted tubules.
• Medulla: Features long tubular structures like ascending/descending limbs of the loops of Henle and collecting ducts.

Identifying Structures in the Renal Cortex

• Renal Corpuscle: Look for the glomerulus inside the glomerular capsule. The inner layer of the capsule contains podocytes.
• Proximal Convoluted Tubule: Characterized by a fuzzy lumen due to the brush border (microvilli) of epithelial cells, which aids in secretion and reabsorption.
• Distal Convoluted Tubule: Distinguished by a clear, open lumen without a brush border. Both tubules consist of simple cuboidal epithelium.

Identifying Structures in the Renal Medulla

• Collecting Ducts: Identified by their thick walls made of simple cuboidal epithelium and a visible lumen.
• Loops of Henle: Much thinner walls compared to collecting ducts, appearing as thin strands of tissue without a clear, large lumen.

Bladder Histology

• Transitional Epithelium: Key feature is its irregular apical profile, resembling "monkey bread", with puffy, disorganized cells. The lumen is above this layer.
• Layers: Below the epithelium is a layer of connective tissue, followed by smooth muscle (detrusor muscle).