histology - kidney, etc Flashcards
how do systems extrinsic to the kidneys affect the kidneys? if sense BP too low <80~~
sympathetic NS -
SNS - what can it do?
carotid sinus - glossopharyngeal, CN 9
aortic sinus - vagus CN 10
message to brain, 2 messages can be sent -
1 - alpha 1 adrenergic receptors on afferent arterioles to CONTRACT
2 - to JG cells - to stim renin - this on beta 1 adrenergic - increases calcium in JG which stim renin production
What does renin do? What is it? Renin is enzyme
aldosterone (glomerulus cortex adrenal0
Angiotensin II, binds to many receptors in the body to affect several systems. It can increase blood pressure by constricting the blood vessels. It can also trigger thirst or the desire for salt. Angiotensin is responsible for the release of the pituitary gland’s anti-diuretic hormone.
liver producing angiotensinogen (protein) -
w/ Renin becomes angiotensin 1
from lungs ACE
becomes angiotensin II
effects adrenal to make ALDOSTERONE
(which creates absorption of sodium - hence BP up) in distal convoluted tubule
in kidney - vasoconstrictor
hence BP up
prox convulated tubes - brush border
microvilli
tons of mitocondria - REABSORPTION -
pinocytic vessels
Osmosis
exocytosis
microvilli - increases surface area, lateral folding and basal invaginations ALL facilitate reaborption and secretion of substances
microvilla - longer than distal, cuboidal, acidophilic PINK
interdigitations
tight junctions - major reabsorption
folds in lateral surface - plicae and
BASAL BORDER invagations and tons of mitrochondria - active transport - ATP
reabsorption function -
all glucose
amino acids
85% NaCL and Hx0, Po4, Ca++
protein
secretions - creatinine (from muscles)
pinocytosis - active ion trasnport NA+/K ATPase
glomerulus
really capillaries - special kind - blood runs thru, and some goes out and becomes urine or starts to become urine
Aquaporin 1
aquaporin-2 (AQP2), located in collecting ducts (
in proximal convulated tubules - 70% water, bulk of solutes
Aquaporin-1 (AQP1), located in proximal tubules (PT) and descending thin limbs of Henle (DTL), and aquaporin-2 (AQP2), located in collecting ducts (CD), are channels involved in water transport across renal tubule epithelia
cortical portion of collecting tubules?
in inner and outer medulla
disorders of Prox conv tubules? PCT
can’t reabsorb - missing ATP
Fanconi syndrome is a rare disorder of kidney tubule function that results in excess amounts of glucose, bicarbonate, phosphates (phosphorus salts), uric acid, potassium, and certain amino acids being excreted in the urine.
fanconi syndrome - hereditary or acquired - fail to reabsorb because decrease in ATP - can’t use the sodium pump
cystinosis - most common cause in kids
cystinosis?
most common in kids???
when reaborbed thru walls - where go?
blood
loop of henle?
thick descending limb - simple cuboidal epith - structural similar to PCT
thick or thin descending lined w?
simple squamous epith
thick ascending -
simple cuboidal - more like distal convulated tubules DCT
four types of epithelial cells
type 1
not much going on
type 1 -
SHORT LOOP nephon
thin descending and ascending thin, simple epith - almost no interdigitations
few / no organelles
type 2
LONG NEPHRON - lots of organelles
Juxtamedullary nephon for types 2,3 and 4
thin descending LONG LOOP many small, blunt microvilli - organelles,
lateral interdig varies on species
cortical labyrinth, taller epithelium -
type 3
inner MEDULLA
thin descending INNER MEDULA, thinner epith, fewer microvilli,
lateral interdigitations absent
type 4
at bend of Loop
and entire thin ascending - flattened epith w/o microvilli, few organelles
type 4
at bend of Loop and up to THICK
and entire thin ascending - flattened epith w/o microvilli, few organelles
function loop henle?
reabsorb !! 15% of filtered water and 25% filters NACl, K+, Ca2+, HCO3-
where urine formed - hypertonic urine, water retention
thin descending p permeable to water
ascending - impermeable to water, but permeable to NA+, K+, CL-
distal convoluted Tubule CVT
Vascular pole
location - continuation of thick ascending, goes back into CORTEX - vascular pole of renal corpuscle - juxtaglmerular region
-
here find?
Macula Densa
DCT?
no brush border
Do have tons of mitochondria
simple cuboidal, smaller thatn PCT, lack brush border, few Microvilli, basal infolding are present with mitochondria
function of DCT
Aldosterone affects here - to reabsorb sodium and water
influence of aldosterone
absorb NA and Hx0
secrete K+
reabsorb bicarb ion and secretion of H+
converts ammonia to amonium
Addison disease? SALTY URINE
aldosterone deficiency - excessive loss of sodium in urine