Page 470 - Concise Pathology for Exam Preparation ( PDFDrive )

16 Diseases of the Kidney and Lower Urinary Tract 455

Distal convoluted tubule

Smooth muscle cells
Macula densa cells
Afferent arteriole

Efferent arteriole
Juxtaglomerular cells

Foot processes
of podocytes

Mesangial cells

Glomerular capillaries
Basal lamina

Urinary space
Podocyte

Parietal layer of Bowman's capsule

FIGURE 16.3. Schematic representation of a renal glomerulus.

Glomerular filtration occurs across the following barrier:
1. Fenestrated endothelial cells lining the capillaries
2. Glomerular basement membrane (GBM) associated with endothelial cells
3. Pores between the foot processes of the podocytes
GFR is influenced by
1. Blood pressure and blood flow
2. Obstruction to urine outflow
3. Hormonal regulation
1. Renin—angiotensin
2. Aldosterone
3. Antidiuretic hormone (ADH)
4. Atrial natriuretic peptide (ANP)
Tubules

The bulk of the renal substance is formed by tubules. The tubular epithelium varies in
different parts of the nephron depending upon their function.
1. PCT: It is the first part of the glomerulus responsible for active reabsorption of filtered
sodium, potassium, glucose, amino acids and proteins, bicarbonate, phosphate,
calcium and uric acid as well as passive reabsorption of water. It arises at the urinary pole

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