Kidney B7 Flashcards
Functional unit of the kidney
Nephron
What is the regulation of water balance equation?
Water intake + Metabolic water = Renal excretion + GI excretion + Evaporation
If positive you gain total body water
If negative you lose total body water
Water always follows what?
Salt
What are some renal functions?
Conserve nutrients- reabsorb glucose, amino acids, etc
Excrete wastes- nitrogenous wastes, ketoacids, H+, drug metabolites
Regulate cardiac output and BP
Control hematopoiesis- release erythropoietin in time of renal hypoxia
Glomerulus is unique because it has what?
Has arteriole capillary arteriole, so there is a very fine tuning supply
What is of nephron is the short loop of Henle, mostly stays out of medulla (80%)
Cortical (superficial)
What is the long loop of henle, can go down to the papilla (20%)
Juxtamedullary Nephron
What are the 2 capillary beds of the nephron?
Glomerular- filters plasma into nephron, makes tubular fluid
Peritubular- normal capillaries fed by efferent arteriole
What is removed from the body via urine?
Remainder of tubular fluid and solutes at end of nephron
Excretion
This moves solutes/water from tubular fluid back to blood
Reabsorption
THis moves solutes from blood into tubular fluid
Secretion
Urinary excretion rate depends on what 3 things?
Filtration rate, Reabsorption rate, secretion rate
What is the site of filtration?
Glomerulus
The things that alter filtration?
Capillary hydrostatic pressure
Tissue is now called Bowman’s space
The majority of important stuff that is filtered in your body is reabsorbed where? Most fluid is reabsorbed here.
Proximal Convoluted Tubule (PCT)
Part of the juxtaglomerular apparatus
Macula Densa (senses tubular fluid flow and renal blood flow)
Where does reabsorption and dilution of urine take place?
Loop of Henle
Where does the fine tuning of urine solute amounts take place? Also site of pH balancing
Distal convoluted Tubule
not pee a lot hormone?
Anti diuretic hormone (ADH)
Where does regulation of water reabsorption and final control of urine osmolarity take place?
Collecting ducts
Excretion= what?
Excretion= Filtration + Secretion - Reabsorption Excretion = urine flow* [urine]
Plasma volume is about ______ of total blood volume
half (40%)
The amount of plasma that has a certain solute removed from it. How much plasma the kidney is able to pull (whatever it is you want out) out of it?
Clearance
Cx= Xu* V/ Xa
Xu= concentration in urine V= urine volume Xa= concentration in blood plasma
Clearance of insulin= ___________________
Glomerular filtration rate (GFR)
Clearance of PAH=
Renal Plasma flow
Will tell you how much plasma has moved through the kidney
How much water we are excreting is what?
Free water clearance
If plasma osmolarity were too high, what would we want?
Excrete low amounts of water
If plasma osmolarity were too low, what would we want?
Want to get rid of urine
Body is overhydrated, is ECF osmolarity high or low? Is free water clearance + or -?
low
positive
Body is dehydrated, ECF osmolarity is high or low? Is free water clearance + or -?
high
negative
Normal plasma osmolarity is around what?
290 or 300
