biol 332 physiology exam 3

urinary system fx

• excretion - removal of organic metabolic waste

• water balance

• electrolyte balance

• conservation of valuable nutrients (glucose)

• control of blood cell formation ( erythropoietin)

• regulation of blood pressure (renin)

• 1 ml/min of urine production

structures of urinary system

• kidney

• ureter

• urinary bladder

• urethra

kidney functions

• regulates extracellular fluid (plasma and intersistual fluid)

• [] of waste product

• [] of electrolytes

• ph of plasma

nutrients and by products

• glucose (C6 H12 O6) → cellular respiration → CO2 and H2O

• lipids (CH3 CH2N COOH) → cellular respiration → CO2 and H2O

• proteins (C H O N ) → CHO respirated but N urinated

types of byproducts

• urea (15 ml/dl)

• creatinine (1 ml/dl)

Uremia

increased levels of urea and creatinine in the blood

renal failure indicator

Blood urea nitrogen test (BUN test)

blood sample test measures nitrogen

renal failure if over 15 ml/dl

internal kidney structure

• renal cortex - outer, granular red brown bc lots of blood flow

• renal corpuscles - in cortex, gives granular shapes bc glomerolus balls

• glomerulus - filters blood

• medulla - inner

• pyramids - striped bc lots of rubules tubules

• columns - between renal pyramids

• calyces - collects urine from renal tubes, minors connect into a major

• pelvis - calyces connect and urine drains

ureters strx and fx

• transport urine from kidneys to bladder

• lined with smooth muscles for peristalsis (contract to push down)

• connect to urinary bladder at an angle to prevent backflow

• membrane flap at urinary bladder to further prevent backflow !

normal urine production rate

1 ml/min but not all become pee

oliguria

less than 1 ml/min urine

diuretics

increase rate of pee production

bp medication bc lower stroke volume

kidney stones

solidified calcium and acid salts (casts) forming stones

start in the kidney, and have to travel down the ureter and bladder and urethra

caused by oliguria, prevented by low salt intake and high water intake

hydronephrosis

really big kidney stones that get stuck in the urinary system, causing ureter and calyces to expand

unilateral- stone stuck in one ureter

bilateral - stone stuck in bladder

renal blood flow

1 L/min, ½ per kidney

from the 20% of blood that goes to kidneys from the 5 L/min of blood from heart

kidney vasculature structure (tracing)

• renal artery - from aorta to kidney

• segmental arteries → interlobar arteries (renal columns) → arcuate arteries (top of cortex) → cortical radiate arteries (interlobular) → microscopic afferent arterioles (1 mil per kidney)

• all branching so its a lot of arteries

glomerulus

• filter site for blood

• fenestrated capillaries - lots of holes that are too small for cells like rbc to escape but fluid can be pushed out

• filtration moves into other tubules system called nephrons

nephrons

system of tubules around the glomerulus

• renal corpuscle - glomerulus + bowmans capsule, always in cortext, filter site, 180l fluid passes but no rbc released

• filtrate out the glomerulus and picked up by bowsman capsute

• afferent arterioles drain blood into glomerulus → fluid and solutes are pushed through the glomerulus and pushed into the bowmans capsule (ig like coffee filter) → remaining filtrate blood in glomerulus is drained by efferent arterioles

• renal tubules - reabsorption and secretion site

• provimal convulated tubule → loop of henle → distal convulated tubule → collecting tubule → collecting duct

compounds not filtered out of glomerulus/stay within capilaries

• rbc

• plasma proteins

• these are the bigger cells in the blood

compounds that will be filtered out of glomerulus/leave capilaries

• water

• sodium

• glucose

• urea

• creatinine

• urorbin

• most of these will be reabsorbed

glomerular hematuria

damaged glomerulus

blood come out of urine,

can cause anemia

non glomerular hematuria

blood from kidney stone, UTI, bladder cancer,

blood come out of urine,

can cause anemia

glomeular dmg test

dysmorphic rbc - glomerular

normal rbc - not glomemrular

proteinuria

dmg to glomerulus, plasma protein come out in urine

hypertension sign

cause edema

filter

blood pushed through glomerulus into nephrone

affects rbc and plasma proteins

reasborption

tubules back bloodstream

affects water, sodium, and glucose

178.5 L of filtrate reasbsorbed

secretion

taken from blood into tubule after filter

excretion

substance from blood, put into tubules, and eliminated

affects urea, creatinine, and urobilin

glomerular filtration rate

indicates how well kidneys work, between filtration and reabsorption

measuring ultra filtrate, h2o, na, glucose, urea, creatinine, urobilin

125 ml per minute

increasing gfr

increasin size of afferent artertionsm, more blood come in and more pressure

decreasing gfr

constricting size of afferent artertiones, decrease blood and less pressure

renal disease

gfr less than 60 ml/min

end stage renal disesae

less than 15ml/min gfr

build up of nitrogen waste in blood

end stage renal disease treatments

• kidney transplant - new working kidneys put into body

• dialysis - connected to machine and filters blood for you

• death - urea or creatinine cannot be removed

water reabsorption site

• proximal convoluted tubule - 80% mandatory water reabsorbed, depends on Na and Glucose

• collecting duct - facilitated water reabsorption, regulated by the body depending on hydration levels given from the pituitary gland

• more/less hydrated → less/more reabsorption → more/less extretion

sodium glucose co transporter

uptakes sodium and glucose and pumps in n out of cell

water follows sodium in n out of cell

anti diuretic hormone ADH

• produced in hypothalamus

• released from posterior pituitary gland

• facilitates water reabsorption and less excretion

collecting duct

• lumen - filtration flow site

• apical - medial

• basal - superficial with blood vessels

• v2 receptor (vasopressin) - basolateral side, adh binds to it

• v2 signal aquaporin - inserts on apical membrane, allows h2o to be absorbed

aquaporins

• water channel proteins on the edges of vesicles

• with adh → fuses with plasma membrane

• without adh → pinches itself off back

flozin

diuretic

antagonize sglt 1 (blocked)

sodium and glucose will not be absorbed, water will not follow, and all be excreted instead

v2 antagonist

diuretics

antagonized v2 in the collecting duct

Aquaporins don’t bind, and vesicles cannot move to reabsorb water

anti anti-diuretic hormone (ethanol)

diuretics

treats hypertension/pulmonary edema → decrease blood vol and lowers bp

Suppresses ADH and does not facilitate water reabsorption → increase excretion (pee)