anatomy 2 Flashcards
kidneys (142 cards)
Wilms’ tumor
kidney tumor assoc. with aniridia
kidney functions
acid base balance, controling Na (&H20) excretion and thereby also controling BP, eliminate waste like urea, uric acid and creatinine, PRODUCE erythropoietin and vitamin D3, degrade insuline and PTH
what % of body weight is water?
60%
what % of body weight is INTRA-cellular
40%
what is in EXTRA-cellular body fluid?
20% and has interstitial fluid, plasma, transcellular, NaCl and NaHCO3
what is macula densa and where is it?
MD monitors fluid composition @ tubular lumen at the JG apparatus (in front of Lacis cells)
what are lacis/ extraglomerular mesanglial cells?
they lie behind macula densa layer at the entrance near Bowman’s capsule–transmit info from macula densa to the granular cells
what are granular cells? aka JG cells?
smooth muscles with epi appears @ AFFERENT arteriole near glomerulus–synthesize renin (vasoconstrictor when low BP)
when do JG cells produce renin?
beta-1 adrenergic stimulation, JG detected low renal perfusion P-meaning when there’s low fluid P at JG, and low NaCl re-absorption by the macula densa due to a low GFR
what is the equation for urine formation?
excreted: filtered - reabsorbed + secreted
what is the quation for renal clearance in word form?
clearance= (urine concentration * flow rate) / plasma concentration—measured in RATIO to clearance of INULIN (same as GFR)
what does it mean to have a LOW clearance? less than 1
low Clearance ratio= need MORE of it in the body= increase reabsorption of product
why do we use inulin for GFR clearance? what’ a normal value?
inuline= fructose polymer that just stays in the tubule and goes to pee, nontoxic and normal= 110-125mL/min
what is GFR?
rate at which plasma is filtered (out into bowman’s and into Prox. tubule) by the glomeruli
what is creatinine? how’s it related to GFR?
from creatine phosphate and is always stable in blood unless there’s disease. has INVERSE relationship w/ GFR
what does high creatinine clearance in pee mean?
good, efficient kidneys! they are working well to maintain stable plasma creatinine levels. low PLASMA creatinine= good filtration= high GFR!
name something that should NOT be in urine?
glucose, protein, AA, RMC, WBC, bilirubin, ketones (acidosis)
what is glucose TH for diabetics?
over 200+mg in pee= diabetic
what type of diabetes is likely in someone with ketones in their urine?
type 1
what is bilirubin?
yellowing in brusing, from break down of blood. Usually means liver problem, but can be in newborns who are making too much RBC and liver is killing off the excess so there’s increase in bilirubin–that’s normal
what % of cardiac output goes to renal blood flow? what is that in L/min?
20% – 1.2L/min
assuming HIGH BP, what is the myogenic mechanism?
Ca channels open and contract smooth vessel walls which decrease the diameter= vaso-CONSTRICTION= increases resistance to “brace” for the high BP
assuming HIGH BP, what is the tubuloglomerular feedback?
highBP= higher GFR to help get rid of some fluid to decrease the P. This happens with ATP released @ macula densa via adenosine release—a vasoconstrictor at the local level (also stops reninproduction which is for low BP)
what are some vasoconstrictors?
renin during low BP, adenosine during high BP, angio2 @ lungs, thromboxane for hemostatis, vasopressin