Renal System Flashcards
Renal Functions: regulation of osmolality
what is normal osmolality and range
300 mOsm/kg
270-310 mOsm/kg
the concentration of what contributes to 90%of the extracellular fluid osmolality?
sodium salts
osmolality is another way of saying what?
sodium concentration
name the 3 endocrine fxns of the kidney
Erythropoietin production
Renin productin
Vitamin D conversion into Vit D3
blood is delivered to the glomerulus via the ______ arteriole and exits the glomerulus via the ______ arteriol
delivered Afferent
Exits Efferent
there are 2 types of nephrons: what are they
cortical nephrons
juxtamedullary nephron
picture of 2 types of nephron
the cortical nephron has short loops of henle and glomeruli located where?
near the surface of the kidney
the juxtamedullary nephrons have LONG loop of henle and the glomeruli is where
deep in the cortex near the the cortical medullary junction
again picture of 2 nephrons
blood passes through the ______ arterioles, the _____ capillaries, the _______ arterioles, and the _______ capillaries before it drains into the venous system
Afferent arteriols
glomerular capillaries
Efferent arteriole
peritubular capillaries
the ______ arteriole branches into a caillary network that entwines the renal tubule
Efferent
the ______ capillaries are the capillaries that arise from the efferent arteriole and engulf the renal tubule
peritubular capillaries
the ____ _____ are the peritubular cappillaries of the loops of henle of the juxtamedullary nephrons, it constitutes a countercurrent echange system
Vasa recta
a substance may be transported FROM the tubule TO the capillary called what
reabsorption
a substance may be transported FROM the tubule TO the capillary called reabsorption or FROM the capillary TO the tubule called what?
secretion
the vasa recta are hairpin-shaped capillaries of the long loops of henle of what nephron
juxtamedullary nephrons
2 parts or divisons of the kidney>
cortex
Medulla
Glomeruli, proximal tubules, and distal tubules are found in what part of the kidney
cortex
the loops of henle and collecting ducts are found in what part of the kidneys
medulla
what part of the outter medulla is most vulnerable to ischemia?
inner stripe
the LOH is a COUNTERCURRENT MULTIPLIER which does what?
creats the osmotic gradient
the vasa recta is a COUNTERCURRENT EXCHANGER what does that mean
it maintains the osmotic gradient created by the LOH
the LOH deposits NaCl in the medullary interstitium and in doing so, produces a gradient in osmolality that increases progressively from 300 to 1200 deep in the medulla. this osmotic gradient is required for what?
making the urine concentrated or making the urine dilute
AVP/ADH:
synthesized where?
hypothalamus (paraventricular and supraoptic nuleus)
AVP/ADH:
stored where?
Post pituitary
(neurohypophysis)
AVP/ADH:
secreted into what?
blood
AVP/ADH:
what is the stimulus for release
increased Na+
Increased osmolality
AVP/ADH:
site of action
collecting ducts
AVP (ADH) is synthesized where in the hypothalamus?
paraventricular and supraoptic nucleus
AVP/ADH is transported in the axoplasmic fluid of the hypothalmic-hypophyseal nerves to storage sites in the nerve terminals where
neurohypophysis
what stimulate the release of AVP/ADH from the posterior pituitary
nerve action potentials
when circulating levels of AVP/ADH are HIGH, what type of urine is formed
a small volume of concentrated (0.5mL/kg/kr)
when circulating levels of AVP/ADH are LOW what is the urine like
large volumes of dilute urine
(25 mL/kg/hr)
what is urine osmolality with HIGH AVP/ADH
1200-1500 mOsm
what is urine osmolality if AVP/ADH is low
50-100 mOsm
what are causes of DI? (2)
failure of AVP/ADH synthesis or release (most common)
Insensitivity of distal tubules and collecting ducts AVP/ADH (nephrogenic)
what are causes of SIADH
result of surgery
intracranial tumor
hypothyroidism
porphyria
Small OATS cell carcinoma
what are the diagnostic signs of SIADH
increased urine Na+ concentration
Increased Urine osmolality
hyponatremia
decreased PLASMA osmolality
(too much ADH pissing out Na+)
Spironolactone is a competitive aldosterone antagonist that works on the late DCT and the collecting decut (mainly collecting duct). it increases excretion of what? and promotes retention of what?
increases Na+ excretion
and promotes K+ retention
Chronic Kidney disease:
what is the best test to determine renal reserve
creatinine clearance (measures GFR)
