Shared Flashcard Set

Details

Histology
Urinary
49
Medical
Graduate
10/07/2008

Additional Medical Flashcards

 


 

Cards

Term
Function of kidneys
Definition
Regulation of blood and extracellular fluid composition, excretion, endocrine
Term
Regulation of blood and extracellular fluid composition
Definition
Water, Ions, Acid-base
Term
Excretion
Definition
Metabolic wastes, all tissues esp liver. Toxins and drugs, often after liver modification.
Term
Endocrine
Definition
Renin: angiotensin proteolytic processing. Erythropoietin: cytokine for CFU-E
Term
Function
Definition
Form initial urine by filtering 180-200 liters/day in renal corpuscle. Recover 80% of initial filtrate volume and solutes, PCT, form high salt concetration in medulla, recover 20% of salt- loop of henle, recover NaCl (aldosterone and secrete acid and bicarbonate- collecting tubules and ducts.
Term
functions
Definition
selectively recover water (ADH) and regulate rate of urine formation- Juxta-glomerular apparatus (JGA)
Term
Nephron
Definition
2 million/ kidney, derived from urogenital ridge.
Term
renal corpuscle
Definition
filter unit of kidney. bounded by bowman's capsule formed by a layer of squamous parietal cells. Has vascular pole (afferent and efferent aterioles).
Term
urinary pole
Definition
beginning proximal convoluted tubule opposite vascular pole.
Term
glomerulus
Definition
lies inside the capsule and consists of fenestrated capillaries link the afferent and efferent arterioles. Mesangial cells found under basal lamina, between adjacent capillaries. Pericyte-like cells may physically support capillaries, turning over basal lamina involved in filtration, helping control capillary diameter by their contractility and secreting vasoactive compounds.
Term
podocytes
Definition
surround that capillaries outside the basal lamina, also called visceral layer.
Term
three layered filter
Definition
fenestrated endothelium pores retain cells, basal lamina retains proteins, 450,000 mw, filtration slits of podocyte pedicles 68000 MW pass smaller proteins and other solutes, blood pressure drives fluid out.
Term
three layers
Definition
basal lamina, endothelial cells, podocyte
Term
Filtration barrier is labile
Definition
pressure of standing up is enough to allow albumin to ender urine. = orthostatic proteinuria
Term
diabetes mellitus
Definition
rate increases then decreases as basal lamina thickens and kidney dysfunction.
Term
Proximal convoluted tubule
Definition
tall cuboidal or columnar cells with apical brush border and junctional complexes. recovers 80% of initial ultrafiltrate. actie Na pumping by Na, K ATPase creates Na gradient used by co-transport system to recover solutes. sugar phosphate, calcium, amino acids NaHCO and water follows
Term
PCT
Definition
protein transport through endocytosis, secrete organic acids penicillin into urine.
Term
straight PT
Definition
enters medullary ray. lower cells with fewer microvilli.
Term
medullary rays
Definition
straight parallel arrays of proximal loop elements and collecting tubules. considered part of the medulla and may contain loops of Henle
Term
distal convoluted tubule
Definition
cells are shorter, wider lumen no brush border more nuclei. some ca dn nacl resorption. thiazide drugs inhibit NaCL in this region and increase uring output, diuresis.
Term
collecting tubules and ducts
Definition
mesonephric tissue. collecting ducts merge to become collecting tubules. Columnar and pale staining. Have distinct lateral cell borders.
Term
aldosterone regulation of sodium collection in collecting tubules and collecting ducts
Definition
made in adrenal cortex, opens apical sodium channels in tubules, letting sodium into the cytoplasm from urine. Basolateral NAKATPase activated, pumps sodium into blood. and potassium into cells from blood. Causes potassium loss to urine and sodium and water resorption in blood Increase blood pressure.
Term
Antiduretic hormone
Definition
water recovery, low- loss of water in urine, high,reduces blood pressure and volume. CT CD waterpermeable and water leaves tubes and and is returned to circulation. Higher blood volume and pressure.
Term
Medullary salt concentration
Definition
high salt concetrates urine
Term
aquaporins
Definition
high water permeability of MCD epithelial cells. ADH low- found in endocytic vessicles. ADH stimulates fusion of these vessicles and plasma membrane- highly permeable to water.
Term
medullary collecting ducts
Definition
H and HCO3 secreted from CD's into urine o regulate blood pH. converge to form papillary ducts which empty into minor calyces at area cribosa. transitional epithelium begins to line the ends of the ducts.
Term
Antidiuretic hormone (vasopressin)
Definition
made in neurohypophesis causes CT CD cells to become water permeable. leaves cells to return to circulation, increases blood pressure.
Term
Juxtoglomerular apparatus (JGA)
Definition
Macula densa cells, Juxtoglomerular cells (modified smooth muscle cells of tunica media store renin) afferent. Extraglomerular messangial cells(EM) lacis of goormaghtigh
Term
tubule flow rate controlled by controlling initial filtration rate.
Definition
total initial filtration rate of both kidneys is GFR- important clinical variable.
Term
tubule flow rate controlled by controlling initial filtration rate.
Definition
total initial filtration rate of both kidneys is GFR- important clinical variable.
Term
MD cells
Definition
monitor sodium concentration in the lumen of TAL. High salt causes AA to constrict. - slows production of initial filtrate, decreasing sodium entry. involves adenosine or ATP. EM cells may mediate response.
Term
Macula densa cells
Definition
signal jG cells to release renin.
Term
renin
Definition
produces angiotensin 1 and 2, which cause constriction of efferent arterioles. Increases production of initial filtrate. MD sends protiglandins as signals to the JG cells.
Term
Renin and angiotensin
Definition
renin- angiotensinogen to angiotensin 1 then to angiotensin 2 by other proteases in lung and elsewhere.
Term
angiotensin 2 raises systemin blood NaCl and pressure
Definition
signals adrenals to release aldosterone- increases sodium and fluid resorption by CT and CD. Constricts arterioles everywhere.
Term
JGA
Definition
contributes to overall blood sodium, volume adn pressure.
Term
constriction of Afferent Arteriole (AA)
Definition
slows the production of initial filtrate, decreasing NaCl entry.
Term
What happens when there is high NaCl in the TAL?
Definition
Macula densa cells secrete adenosine to constrict the AA, which decreases the filtration pressure and initial filtrate, which decreases the amount of NaCl in the filtrate in JGA. This slows the amount of urine made.
Term
Low sodium in the TAL?
Definition
Macula densa cells signal JG cells to release renin-> angiotensin 1->angiotensin 2-> which increases aldosterone, which causes greater constriction of efferent arterioles than afferent, which increases production of initial filtrate by increasing filtration pressure, increases NaCl recovery, increases BP.
Term
Angiotensin 2
Definition
raise systemic blood sodium and pressure. Signals adrenals to release aldosterone, increasing sodium and fluid resorption by collecting tubules and ducts.
Constricts Arterioles EVERYWHERE, but particularly efferent arterioles. Raises blood pressure by constriction and by increasing blood volume and body fluids in general.
Term
Blood flow in the kidney
Definition
Renal artery, segmental artery, Interlobar atery, arcuate artery, interlobular artery, afferent arteriole, fenestrated capillaries in glomerular capillaries, efferent arteriole, (vasa recta or peritubular capillary network depending on if you are in the juxtamedullary glomeruli or cortical glomeruli, respectively)
Term
efferent arterioles of juxtamedullary glomeruli
or counter current exchange system
Definition
supply vasa recta. Medullary arteriolae and venae rectae run into the medulla parallel to each other with fenestrated endothelium connecting them. Allows blood supply to medulla without removing the high salt concentration of the extracellular fluid in the medulla.
Term
kidney interstitial cells
Definition
fibroblast-like, synthesize little extracellular matrix. Secrete erythropoiten (EPO)- stimulates red blood cell production and prostiglandins. Are adapted to high salt concentrations.
Term
External collecting system
Definition
bladder, urethra, ureters
Term
layers of the external collecting system
Definition
Transitional epithelium (diffusion barrier)
Layers are inner mucosa, middle muscularis, external adventitia.
Term
Ureter layers (major and minor calyces, renal pelvis, and ureter proper)
Definition
Mucosa: transitional epi : 2-3 cells thick in minor calyces, 4-5 in ureter proper. Lamina propria- dense collagenous connective tissue.. No submucosa. Muscularis- two layers, inner longitudinal, outer circular with bundles of smooth muscle cells. In lower 1/3 of ureter an additional layer of smooth muscle is added (longitudinal). Finally, adventitia.
Term
Bladder layers
Definition
Mucosa: 6 layers of transitional epitheium. lamina propria: dense collagenous connective tissue. No submucosa. Muscularis: three layers with complex orientation. Middle layer is most prominent. Adventitia: upper portion covered with connective tissue and mesothelium= serosa.
Term
Urethra male
Definition
prostatic portion lined with transitional epithelium. Membranous part through urogenital and pelvic diaphragm lined with columnar (stratified and psuedostratified) columnar epithelium. Spongy portion psuedostratified columnar epi.
Term
Female Urethra
Definition
lined with squamos stratified epithelium. Nests of mucous glands may be found.
Supporting users have an ad free experience!