Chapter 26 urinary
Podocytes
modified simlple squamous epithelium cells found in the visceral layer of glomerular capsule
encircles the capillaries and forms a leaky barrier called filtration membrane
podocytes
excretion of metabolic wastes and foreign substances, regulation of blood ionic composition, blood pH, blood volume, BP, blood glucos level. Maintenance of blood osmolarity and produces calcitrol and erythropoietin
Homeostatic Kidney Functions
calcitrol-active form of Vit D that helps regulate calcium homeostatis
Erythropoietin-stimulates RBC production
Hormons produced by kineys
Renal Cortex
superficial, extends from the renal capsules to the base of pryamids, divided into an outer cortical zone and an inner juxtamedullary
Renal Columns
extentsions beteen the pyramids
Renal Medulla
deeper region, consists of several pyramids and renal papilla faces the hilum
Parenchyma
functional portion of the kidney that is formed by the renal cortex and renal pyraminds of the medulla
Nephrons
functional untis of the parenchyma
responsible for filtering blood and producing urine
nephrons
Papillary ducts
extend through the renal papillae of the pyraminds
drain into the minor and majpr calyces
papillary duct
where blood the nephrons filter drains into
papillary ducts
Minor/Major Calyces
onces filtrate enters, it becomes urine because no furhter absoprtion can occure due to change in epithelium to transistional
cup-like structures that the papillary drain into in each kidney
minor/major calyces
Renal pelvis
a single large cavity where urine from the major calyces drains into
the urine from the renal belvis drains into...
uters and bladder
renal sinus
a caivty that the hilum expands into
contains part of the rena pelvis, calyces and branches of the renal blood vessels and nerves
renal sinus
renal hilum
where the renal artery and vein pass into the functional portion of the kidney
Cortical nephron
contstitute 80 to 85% of nephrons
CT that surrounds each kidney
renal capsule, adipose, fascia
dense, irregular CT continuous witht her ureter that acts as a barrier against trauma and helps maitain kidney shape
renal capsule
fatty tissue that protects kidney from trauma and holds kidney firmly in place
adipose capsule
dense, irregular CT that anchors kidney to surrounding structures and abdominal wall
renal fascia
Juxtamedullary nephrones
contstitute 15% of neprhons
receives blood from pertibular capillaries and vasa recta
juxtamedullary nephrons
as an ascending limb that goes from thin to thick
juxtamedullary nephrons
Renal corpuscle
consist of glomerulus and the glomerular (Browman's capsule)
Glomerular (Bowmans) capsule (renal corpuscle)
doubled-wall epithelial cup that has a visceral layer of podocytes which wrap around the capillaries
Glomerulus (renal corpuscle)
mass of capillaries that is fed by the afferent arteriole and drains in the efferent ateriole
produces the glomerular filtrate
glomerulus
Net Filtration Pressure
total pressure that promotes filtration
NFP=GBHP-CHP-BCOP
Net Filtration pressure
the mucous menbrane in ureter so it can stretch to accommodate urine volume
transitional epithelium
Albuminuria
albumin in urine; glomerulonephritis, pregnancy, exertion
Glycosuria
glucose in urine; DM DI, excess sweet intake
Casts in urine
glomerulonephritis
Bilirubin in urine
hepatits, cirrhosis of liver
Hematuria
blood cells in urine; kidney stones, cystitus
hemoglobinuria
Hgb in urine: hemolytic anemia
Pyuria
pus in urine; gonorrhea, pyelonephritis
Ketonuria
ketones in urine; starvation
Capsular hydrostatic pressure (CHP)
hydrostatic pressure of fluid in the capsular space against the filtration membrane; 15mmhg; opposes filtration
Blood colloid osmotic pressure (BCOP)
opposes filtration due to the presence of proteins; 10mmHg
Glomerular blood hyrdostatic pressure (GBHP)
BP in glomerular pressure; promotesfiltration by forcing water and solutes in blood plasma thru filtration 55mmHg
osmalarity in the tubule increases in the descending limb, decreases in the ascending limb and decreases more in the collecting duct
diluted urine
urea, uric acid, creatine
major nitrogenous waste
depends on the osmotic gradient of solutes in the blood
concentrated urine
when water flows out the collecting ducts into the interstitial fluid and the tubular fluid becomes...
concentrated urine
glomerular capsule-proximal convoluted tubule-loop of Henle-distal convoluted tubule-collecting ducts
filtrate flow
Juxtaglomerular apparatus
consists of juxtaglomerular cells and the macula densa
glomerular filtration rate (GFR)
amount of filtrate formed by both kidneys each minute
Angiotensin II (GFR regulation)
constricts afferent and efferent arterioles. decreasing GFR
secreted in response to stretch of the cardiac atria which relaxes mesangial cells, increasing capillary surface area and GFR
Atrial Natriuretic Peptide (ANP) (GFR regulation)
Urinalysis
analysis of the volume, physical, chemical, and miscropic properties of urine
Urinary incontinence
a lack of voluntary control over mictruition
once filtrate enters, it becomes urine
calyces
Angiotensin Coverting enzyme (ACE)
converts Angiotensin I into Angiotensin II when it enters into the lungs
vasoconstriction of afferent arteriole
Angiotensin II
enhances reabsorption of Na+ and water in PCT
Angiotensin II
reabsorb more Na+ amd secretes more K+ and H+
Angiotensin II
Renin
removes angiontensin I from the inactive zymgen when BP decreases
activates the renin-angiotensin pathway to increase BP
Renin