Class Notes (836,583)
Canada (509,859)
Biology (1,140)
BIOL 1104 (30)
Lecture

Renal Histology

3 Pages
128 Views
Unlock Document

Department
Biology
Course
BIOL 1104
Professor
Tamy Superle
Semester
Fall

Description
Renal Histology--Dintzis GROSS ANATOMY - Kidney cortex: contains distinctive glomeruli, convoluted tubules, parts of collecting ducts - Kidney medulla: below the cortex, contains limbs of Henle & collecting ducts - Medullary ray: groups of collecting ducts that extend from cortex to medulla - Calyx: terminal expansions of ureter in the kidney, minor calyces meet up with papilla (papilla →minor calyx →major calyx →pelvis →ureter) - Papilla: termination of collecting duct into a minor calyx - Lobe: a medullary pyramid and the overlying cortex - Lobule: lateral borders marked by medullary rays - Arteries in order: abdominal aorta, renal artery, interlobar, arcuate, interlobular, intralobular, afferent arteriole, glomerulus, efferent arteriole, vasa recta RENAL CORPUSCLE - Renal corpuscle: glomerulus + Bowman’s capsule - Glomerulus: tufts of capillaries with fenestrated (“holey”) endothelium - Parietal Epithelium: squamous pariental epithelium of Bowman’s capsule that’s continuous w/ epithelium of proximal tubule - Visceral Epithelium: composed of podocytes - Podocytes: easily seen at border of glomerulus, obvious under EM, have filtration slits that act as filtration barrier; Fxn: manufacture basement membrane, provide filtration support - Mesangial cells: produce & breakdown basement membrane; uptake macromolecules; can respond to local injury; embedded in mesangial substance (stains bright purple/blue—PAS-positive) - Basement membrane: very thick (3500A), PAS-positive, trilaminar (lamina rara interna, lamina densa, lamina rara externa), primary glomerular filtration barrier o Contains type IV collagen, glycoproteins, & proteoglycans * Blood must pass through 1) endothelium, 2) basement membrane, 3) podocyte feet, before entering bowman’s space TUBULES Cortical nephrons—shorter loops, common Corticomedullary nephrons—less numerous, long loops, key in establishing gradient - Proximal convoluted tubule: longest thickest tubule, reabsorbs ~80% H2O & salts as well as all Glu, aa, & proteins; secretes organic cations/anions o Prominent brush border of microvilli for reabsorption (PAS+) o Tall columnar cells w/ interdigitation of cell surfaces o many mitochondria arranged perpendicular to basement membrane - Descending Thick Limb of Henle: sim. to proximal convoluted tubule - Thin limb of Henle: may be hard to distinguish from vasa recta (thin limb has thicker basement membrane than vasa recta), ascending (ATL) and descending (DTL) limbs cannot be distinguished 1 o Thick, PAS+ basal lamina o Low, cuboidal cells or squamous epithelium o DTL & ATL differ in permeability to H2O & salts - Thick ascending limb of Henle: active Na pumps => salt reabsorption but impermeable to H2O; o NO brush border; many mitochondria => striations o Eosinophilic cytoplasm - Distal convoluted tubule: sensitive to aldosterone (=> increased salt reabsorption) excretes K+; helps maintain acid-base balance o PAS stains heavier than collecting duct, cells smaller than collecting duct o Cuboidal cells w/ no brush border; abundant mitochondria - Collecting duct: columnar cells w/ sharp lateral border, no brush border, pale under PAS (paler than distal convoluted tubule), cells larger than distal convoluted tubule o Principal cells—remove H2O from filtrate; dependent on ADH for aquaporin placement in apical cell membranes o Intercalated cells—secrete & resorb protons - Macula densa: part of thick ascending limb that abuts vascular pole of
More Less

Related notes for BIOL 1104

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit