Clinical note: The inflammatory condition known as glomerulonephritis results from an autoimmune cross reaction on the part of the host against streptococcal antigens. Infections triggering this reaction can occur in either the skin or throat. The inflammatory response is largely confined to the glomeruli, damaging the capillaries and basal laminae to the extent that proteins and erythrocytes may appear in the urine. The injury results from antigen-antibody complexes getting stuck in the glomerular filter.

After studying the figures and slides of the kidney, see i you can name the epithelial type and major function of each of the following:

• PCT:
• Loop of Henle, thin limb:
• Loop of Henle, thick limb:
• DCT:
• Collecting tubule:

How do the histological features at different levels of the nephron correlate the major cellular activities or functions at these regions?

Examine glomeruli and se if you can  locate one showing the juxtaglomerular apparatus.

• Identify the macula densa in the distal convoluted tubule.
• Try to identify the specialized smooth muscle juxtaglomerular cells and the lacis cells (Fig. 19-12), although these will be difficult to find in most glomeruli.

What does the juxtaglomerular apparatus do and how does it do it?

Now for the ureter and urinary bladder.