i_01.1. Kidney
(hematoxylin-eosin)
1. General view, low magnification:
- identify a thin connective tissue capsule (renal capsule), renal cortex and renal medulla;
- renal cortex contains renal corpuscles, proximal and distal convoluted tubules and medullary rays;
- renal medulla includes straight tubules of the descending and ascending limbs of the nephron loop as well as collecting ducts;
- learn to recognize arcuate arteries and veins following along the boundary between the renal medulla and the renal cortex, and interlobular (or cortical radiate) arteries and veins.
- Draw and sign::
I - renal cortex (1 – renal capsule, 2 – renal corpuscle, 3 – convoluted tubules, 4 – medullary ray, 5 – interlobular vessel);
II - renal medulla (6 – straight tubules, 7 – interlobular artery, 8 - interlobular vein).
2. High magnification:
- Examine the structure of renal cortex in details:
- in renal corpuscle you will recognize the glomerulus and the layer of parietal squamous cells which bounds the glomerulus capsular space (Bowman’s space),
- proximal tubules are 40–60 μm in diameter$ they have a relatively small lumen and are lined by cuboidal (or columnar) cells having a prominent brush border (basal part of the cell has folded basilateral border);
- distal tubules are 30–50 μm in diameter; unlike the proximal tubules, they have a much larger lumen (cuboidal cells lining them do not have a brush border);
- identify the macula densa of the juxtaglomerulary nephron located in the wall of the distal tubule, at the point where the tubule comes in contact with the glomerulus.
- In renal medulla look for straight tubular segments:
- descending limb is a tubule (13-15 μm in diameter) lined by low cuboidal or squamous cells;
- collecting ducts are identified by a tall, eosinophilic, simple columnar epithelium; lateral cell boundaries are distinct in a collecting duct, and a brush border is absent.
- Draw and sign: 1 – renal corpuscle, 2 – glomerular capillary endothelium, 3 – capsular epithelium, 4 – nephron proximal tubular segment, 5 – nephron distal tubular segment, 6 – macula densa of juxtaglomerular complex, 7 - descending limb of nephron loop, 8 – collecting duct.
3. Define and write significant features of the slide.