Page 729 - Atlas of Histology with Functional Correlations

Consists of capillaries called glomerulus and double-layered glomerular

(Bowman) capsule
Visceral layer of capsule contains podocytes that invest fenestrated
glomerular capillaries
Podocytes exhibit primary processes from which arise smaller pedicles
Pedicles form filtration slits around capillaries that are spanned by filtration

slit diaphragm
Parietal layer is lined with simple squamous epithelium of the glomerular
capsule

Between parietal and visceral layers is the capsular (urinary) space for
glomerular filtrate
At vascular pole, afferent and efferent arterioles enter and exit the renal
corpuscle
At opposite urinary pole, ultrafiltrate enters the proximal convoluted tubule

Blood Filtration

In renal corpuscle, it is through glomerular capillaries
Consists of capillary endothelium, basement membrane, and

podocytes/pedicles
Glomerular filtrate enters capsular space between parietal and visceral layers

Filtration Barrier in Glomerulus

Glomerular endothelium is fenestrated and permeable except for blood cells
and large proteins
Basement membrane restricts molecules the size of albumin

Slit diaphragms between pedicles contain the transmembrane protein nephrin
Filtration slits responsible for glomerular permeability because of size-
selective molecular filters

Renal Tubules

From capsular space, glomerular filtrate enters renal tubules that extend to
collecting ducts
Initial tubule is the proximal convoluted tubule that starts at the urinary pole

of renal corpuscle

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