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Physiology II
-protein in extracellular fluid is
albumin
-plasma in extracellular fluid
-lymphatic would draw out protein
from interstitial spaces
-should not be dumping protein from
capillaries into interstitial
-reflection--basement membrane has a
negative charge and repulses the protein which has a positive charge
-reflection coefficient
-don't
pass=1
-passes
somewhat=.5
-all
pass through=0
-some tissues have a higher
reflection coefficient than others
ex: brain--blood brain barrier; liver high
exchange
-transcellular fluids--pleural,
ocular, CSF (look in index)
synovial
fluid
-controlled by lymphatic drainage or
a specific drainage system
1.
pleural fluid--lubrication and adherence--drainage by negative pressure in the
lungs--adhesions (like two pieces of glass stuck together when they are wet
-neumothorax--air
or extra fluid in this thin pass of the lungs
-pleurasis--inflammation
in lung walls--inflamed tissue rubbing on each other
-pleural space can become filled due
to congestive heart failure, infections, loss of tissue osmolarity, etc.
-minor
fluid, but major factor when impeded
2. CSF
-circulates,
surround the brain, cushioning of brain, enclosed circuit
-when
disrupted
-contra-coue--hit
in front of head and the brain hits the back--occipital lobe is in back and
disrupts vision
-300-500ml/day
produced, vault can hold 125ml
-drain
off required, but a closed environment
-Arachnoid
villi (granulations) areas that are more permeable and allow drain
off--obstructed and accumulate CSF--communicative hydrocephaly (excessive fluid
in CNS)
-alters
in CSF amount of fluid is extremely painful
-no
pain receptors in brain tissue, but the meninges are highly innervated this is
what is painful
-synthesized
in Chroid plexus
-granulations
in center of brain--active transport process of Na+, Cl- and H2O
-drain into 3rd ventricle into
aqueduct to of Sylvius, foramen of Luschka
-fluid
can't circulate
-non-communicative
hydrocephaly--being synthesized and can't move, pressure accumulates
3. ocular fluid
-aqueous
humor--ciliary bodies, drains off
-vitreous
humor--maintains structure of eye--gelatinous substance
-glaucoma--aqueous
humor increased, increasing the optic nerve
-synthesized,
space for 1.5ml, produce more
-basically
salt water
-canal
of Schlem--drainage of aqueous humor--obstruction of this canal
-control-go
in and open canal or use drops to impede production of aqueous humor
Control of Body Fluid Status
-urinary system
-body fluid volume controlled
-lymphatics drain back into the
blood volume
-Starling--kidney was like it has a
brain of its own, regulates on a very narrow window
-3 concepts
1. filtration--what controls filtration through
glomeruli--capillary pressure
2. absorption--tubular structure of the kidney,
very specific, different areas select for different molecules
3. secretion
-anatomical properties
-2
kidneys
-renal
artery brings in blood
-ureter--carries
away waste
-bladder
-urethra
Kidney
-processes
180L/day (8.5-9L of blood)
-blood
filtered 20x a day (about once a day)
-kidneys
fail, everything backup
-excrete
1.5L/day (about 1%)
-reabsorb
99%
-cortex--outer
layer, encapsulated
-medulla
-pyramids--defined
tissue spaces
-nephron--fxnal
unit--1 million
-if
one pyramid is screwed up, still have the rest to fxn
-can't
survive w/ no kidneys
-fluid
and ionic balance
-renal
pelvis--minor calyx and major calyx
-collecting
ducts
-ureters
-kidney
stone--insoluble substances--calcium oxylate
-nephron
-glomerulus
is controlling factor
-filter
plasma into tubule
Arcuate
artery, interlobular artery, arcuate vein, interlobular vein
-glomerulus
sits on top of distal tubule
-Bowman's
capsule collects what comes out of glomerulus
-selective
permeability--
-proximal
tubule--convoluted surface--absorption, 60% reabsorbed of what is filtered
across collecting duct
-a
lot of mitochondria--active transport
-thin, puny tissue, few
mitochondria, descending loop, permeable to water--passive osmosis--ascending
loop
-ascending loop--few mitochondria,
Na+ permeable only
-mitochondria to create gradient for
passive diffusion (active transport)
-distal tubule--convoluted surface,
mitochondria, active transport (only movement) secretion of K+ and H+, reabsorb
Na+
-collecting duct--some mitochondria,
principle cells K+, intercolated cell H+ (pH), permeable to water b/c Adh
-ascending
loop controls the reabsorption of water
-Adh
present w/no osmotic gradient, no reabsorption
-Adh
lets you absorb water
-diurease--getting
rid of fluid, affect ascending loop
-