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BE320 - Exam 3
Sherwood Ch. 14 & 15, Rhoades Ch. 30
183
Physiology
Undergraduate 3
01/28/2012

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Term
ACE inhibitor drugs
Definition
block actino of the angiotensin-convertying enzyme; decrease Na+ reabsorption; help treat hypertension and congestive heart failure
Term
ATP
Definition
high-energy phosphate compound; primary energy source for skeletal muscle
Term
Bowman's capsule
Definition
beginning segment of nephron's tubular component; expanded, double-walled invagination that cups around the glomerulus to collect fluid filtered from the glomerular capillaries
Term
Bowman's capsule hydrostatic pressure
Definition
pressure exerted by the fluid in this initial part of the tubule; tends to oppose glomerular filtration; average = 15mmHg
Term
Henderson-Hasselbalch equation
Definition
pH = pK + log[HCO3-]/[H2CO3]; relationship between [H+] and the members of a buffer pair
Term
Na+ load
Definition
total amount of Na+ in the body fluids, not the concentration of Na+ in body fluids
Term
V_O2
Definition
oxygen consumption in L/min
Term
acetyl coenzyme A
Definition
product of glycolysis that can be used in citric acid cycle or lactic acid cycle to release more energy
Term
acid-base balance
Definition
the precise regulation of the free hydrogen ion concentration in the body fluids
Term
acidosis
Definition
whenever blood pH falls below 7.35
Term
acids/acidic
Definition
group of hydrogen-containing substances that dissociate, or separate, when in solution to liberate free H+ and anions; strong = greater tendency to dissociate/ pH < 7
Term
active reabsorption
Definition
takes place if any one of the steps in the transepithelial transport of a substance requires energy; net movement occurs against concentration gradient
Term
acute renal failure
Definition
characterized by a sudden onset with rapidly reduced urine formation until less than the essential is being produced per day; can die or reversible
Term
adrenal cortex
Definition
endocrine gland that produces several different hormones, including aldosterone
Term
aerobic metabolism
Definition
breakdown of organic fuel (fat, carbohydrates, proteins) using oxygen; involves glycolysis, CAC, and ETC
Term
afferent arterioles
Definition
divisions of the renal atery, one supplies each nephron, delivers blood to the glomerulus
Term
aldosterone
Definition
increases Na+ reabsorption by the distal and collecting tubules; promote insertion of Na+ channels in the luminal membrane and additional Na+/K+ ATP-ase carriers in basolateral membranes;
Term
aldosterone receptor blockers
Definition
decrease Na+ reabsorption; help treat hypertension and congestive heart failure
Term
alkalosis
Definition
when blood pH is above 7.45
Term
ammonia (NH3)
Definition
secreted by tubular cells of kidneys when acidosis exists; enable the kidneys to continue secreting H+ ions
Term
ammonium ion (NH4+)
Definition
ion formed when NH3 and H+ combine; tubular membranes aren't permeable to, so excess H+ combines with this and is excreted
Term
anaerobic metabolism
Definition
breakdown of organic fuel (fat, carbohydrates, proteins) without oxygen; involves glycolysis and lactic acid cycle
Term
anaerobic threshold
Definition
level above which pyruvate—an intermediate product of anaerobic metabolism—is produced faster than it can be used aerobically; unused pyruvate splits into lactate (lactic acid) and positively charged hydrogen ions
Term
angiotensin I
Definition
activated form of angiotensinogen that is activated by renin in RAAS
Term
angiotensin II
Definition
converted from of angiotensin I; converted by ACE during RAAS; main stimulus in secretion of aldosterone from adrenal cortex; constrictor of systemic arterioles --> increase blood pressure; stimulates thirst and vasopressin secretion
Term
angiotensinogen
Definition
plasma protein synthesized by liver and always present in plasma in high concentration; inactive form of angiotensin I; activated by renin; part of RAAS
Term
angtiotensin-converting enzyme (ACE)
Definition
converts angiotensin I to angiotensin II in the pulmonary circulation
Term
aquaporins (water channels)
Definition
passive H2O channels formed by specific plasma membrane proteins in the tubular cells; always open in proximal tubule; channels in distal and collecting tubules are regulated by vasopressin;
Term
ascending limb (loop of Henle)
Definition
actively transports NaCl out of the tubular lumen into interstitial fluid; always impereable to H2O
Term
atrial natriuretic peptide (ANP)
Definition
used in system to oppose RAAS; induces excretion of large amounts of sodium in the urine; stored in granules in specialized cardiac atrail muscle cells; released when the heart is mechanically stretched by expansion of the circulating plasma volume when ECF is increased
Term
autoregulation
Definition
intinsic regulatory mechanism initiated in the kidneys that control the GFR
Term
balance concept
Definition
matching input and output of a substance; important in maintain homeostasis
Term
base/ basic
Definition
substance that can combine with a free H+ and thus remove it from solution; strong = bind more readily with H+/ pH>7
Term
basement membrane
Definition
acellular gelatinous layer composed of collagen and glycoproteins; sandwiched between glomerular and Bowman's capsule; collagen provides structure and glycoproteins' (-) charge repel albumin and other plasma proteins
Term
basolateral membrane
Definition
membrane of tubule wall that faces the interstitial fluid at the base and lateral edges of the cell
Term
blood urea nitrogen (BUN)
Definition
clincial measurement used as crude estimate of kidney fucntion
Term
causes of renal failure
Definition
infectious organisms; toxic agents; inappropriate immune responses; obstruction of urine flow; insufficient renal blood supply
Term
chemical buffer system
Definition
mixture in a solution of two chemical compounds that minimize pH changes when either an acid or base is added or removed from the solution
Term
chemoreflex
Definition
increases sympathetic neural outflow to the heart and systemic arterioles in response to lactic acid produced when dynamic exercise increases in intensity
Term
chronic renal failure
Definition
characterized by slow, progressive, insidious loss of renal function; irreversible
Term
collecting duct (tubule)
Definition
last segment of coduct draining fluid from up to to eight separate nephrons; plunges down through medulla to empty fluid into the renal pelvis; after distal tubule
Term
compensation for metabolic alkalosis
Definition
chemical buffer, respiratory system, kidneys if it persists
Term
compensation for respiratory acidosis
Definition
chemical buffers, kidneys
Term
compensation for respiratory alkalosis
Definition
chemical buffers, respiratory system, kidney if lasts for few days
Term
compensations for metabolic acidosis
Definition
chemical buffers, respiratory system, kidneys excrete more H+ and conserve more HCO3-
Term
concentric contraction
Definition
chronic, low-grading loading, brief, high-intensity muscle contractions caused as it contracts
Term
cortical nephrons
Definition
lie in outer layer of the cortex; loop of Henle dips only slightly into medulla; 80% of nephrons
Term
countercurrent exchange
Definition
passive exchange of solutes and H2O between the two limbs of the vasa recta and the interstitial fluid; preserves the vertical osmotic gradient in the reanal medulla while supplying area with blood
Term
countercurrent multiplication
Definition
concentrating mechanism of the loop of Henle
Term
creatinine
Definition
endogenous material often used to find rough estimate of GFR; not as good as inulin because some is secreted...
Term
descending limb (loop of Henle)
Definition
highly permeable to H2O; does not actively extrude Na+ (does not reabsorb), only segment of tubule that doesn't
Term
diabetes insipidus
Definition
disease characterized by a deficiency of vasopressin; kidneys don't conserve enough water and dehydration and hypertonicity insue
Term
dissociation constant (K)
Definition
same proportion of a particular acid's molecules always separate to liberate H+; = [H+][A-]/[HA]
Term
distal tubule
Definition
segment of tubular component of nephron; tightly coiled, entirely in cortex; after juxtaglomerular apparatus, before collecting duct
Term
diuretics
Definition
therapeutic agents that cause diuresis (increased urinary output) and thus promote loss of fluid from body; function by inhibiting tubular reabsorption of Na+
Term
dynamic exercise
Definition
muscle activation involving rhythmic cycles of contraction and relaxtion
Term
eccentric contraction
Definition
lengthening of muscle by external forces
Term
efferent arterioles
Definition
glomerular capillaries rejoin to form; carries unfiltered blood from the glomerulus; only arterioles in body that drain from capillaries
Term
excretion
Definition
process of discharging waste matter from the blood, tissues, or organs
Term
external urethral sphincter
Definition
layer of skeletal muscle encircling the urethra; part of voluntary urination mechanism
Term
extracellular fluid (ECF)
Definition
fluid surrounding the cells
Term
filtered load
Definition
quantity of any substance filtered per minute; = plasma conctration * GFF
Term
filtration
Definition
undesirable constituents are removed by adsorption into the Bowman's capsule
Term
filtration coefficient (Kf)
Definition
glomerular surface area available for filtration and glomerular membrane permeability
Term
filtration fraction
Definition
fraction of plasma flowing through the glomeruli that is filtered into the tubules; = GFR/renal plasma flow; average = 20%
Term
filtration slits
Definition
created by podocytes; passageway through which fluid leaving the glomerular capillaries can enter the lumen of Bowman's capsule
Term
fluid balance
Definition
maintained by regulation of ECF volume and ECF osmolarity
Term
fluid shifts
Definition
rapid shift from one compartment of body fluid to another in response to imbalance concentrations of solutes or osmolarity
Term
free hydrogen ion concentration
Definition
unbound hydrogen atoms carrying a positive charge that indicate acidity level
Term
functions of kidney
Definition
maintain H2O balance, maintain proper osmolarity of body fluids, regulate the concentration of most ECF ions, maintain plasma volume, proper acid-base balance, excreting waster products, excrete foreign compounds, produce erythropoietin, produce renin, convert vitamin D to active form
Term
glomerular capillary blood pressure
Definition
fluid pressure exerted by the blood within the glomerular capillaries; ultimately depends on the contraction of the heart and the resistance to blood flow; higher pressure than other capillary loactions; tends to push fluid out of the glomerulus into Bowman's capsule; average = 55mmHg
Term
glomerular capillary wall
Definition
consists of a single layer of flattened endothelial cells; many large pores; 100 times more permeable to water and solute than other capillaries
Term
glomerular filtration
Definition
first renal process; blood flows through the gomerulus, protein-free plasma filters through the glomerular capillaries into Bowman's capsule; 20% of plasma that enters the glomerulus is filtered
Term
glomerular filtration rate (GFR)
Definition
rate of filtration; depends on the net filtration rate, glomerular surface area, and permeability of glomerular membrane; GFR = Kf * net filtration rate; average male = 125 mL/min; average female = 115 mL/min
Term
glomerular membrane
Definition
three layers: glomerular capillary wall, basement membrane, inner layer of Bowman's capsule; sieve that retains the blood cells and plasma proteins but permits H2O and solutes of smaller dimension to filter through
Term
glomerulus
Definition
vascular component of the nephron; ball-like tuft of capillaires through which part of the water and solutes is filtered from blood passing through
Term
glycogen
Definition
highly branched polysaccharide of glucose chains, the chief carbohydrate storage material in animals, stored primarily in liver and muscle
Term
glycolysis
Definition
anaerobic enzymatic conversion of glucose to the simpler compounds lactate or pyruvate, resulting in energy stored in the form of ATP, as occurs in muscle
Term
granular cells
Definition
specialized smooth muscle cells of the afferent arteriole in the juxtaglomerular apparatus region that contain many secretory granules
Term
hypertonic
Definition
too little water relative to solute load; too concentrated osmolarity above 300mosm/liter
Term
hypertonicity
Definition
of the ECF, the excessive concentration of ECF solutes; usually associated with dehydration
Term
hypothalamic osmoreceptors
Definition
located near vasopressin-secreting cells and thirst cell; monitor osmolarity of the fluid surrounding them; main excitatory input for vasopressin secretion and thirst
Term
hypotonic
Definition
too much water relative to solute load; too dilute osmolarity below 300mosm/liter
Term
hypotonicity
Definition
of the ECF, usually associated with overhydration; surplus of water
Term
inner layer of Bowman's capsule
Definition
cosists of podocytes that interdigitate with each other to create filtration slits for the fluid leaving glomerulus and enter Bowman's capsule
Term
input
Definition
ingestion or metabolic production of a substance
Term
insensible loss
Definition
loss of water which the person has no sensory awareness of; occurs in lungs and nonsweating skin
Term
insulin sensitivity
Definition
systemic responsiveness to glucose
Term
internal pool
Definition
quantity of any particular substance in the ECF; increased by transferring more in from the external environment or by metabolically producing it; removed by being excreted or by being used up in a metabolic reaction
Term
internal urethral sphincter
Definition
smooth muscle; under involuntary control; last part of the bladder; closed when bladder is relaxed
Term
interstitial fluid
Definition
fluid in the spaces between cells ; bathes and makes exchanges with the tissue cells; 4/5 of ECF
Term
intracellular fluid (ICF)
Definition
fluid within the cells
Term
intrarenal baroreceptors
Definition
1 of 3 inputs to RAAS; senstive to pressure changes within the afferent arteriole; fall in pressure --> increase renin secretion
Term
inulin
Definition
harmless foreign carbohydrate produced by Jerusalmen artichokes; freely filtered and not reabsorbed or secreted; used to determine the GFR; clearance rate of = GFR
Term
isometric exercise
Definition
muscle contractions at constant length and with constant force development
Term
isotonic
Definition
fluid balance of H2O and solute concentration in body fluids is normal at 300milliosmols/liter
Term
juxtaglomerular apparatus
Definition
segment of tubular component of nephron; stucture lies next ot the glomerulus; plays important role in regulating kidney function; comes after ascending loop of Henle, before distal tubule
Term
juxtamedullary nephrons
Definition
lie in the inner layer of the cortex, next to the medullary; loops of Henle plunges through the entire depth the of medulla; has vasa recta; 20% of nephrons
Term
kidneys
Definition
pair of bean-shaped organs that lie in the back of the abdominal cavity, one on each side of vertebral column, slightly above waistline; acts on plasma fowing through it to produce urine
Term
lactic acidosis
Definition
during very intense dynamic exercise when lungs cannot excrete sufficient CO2 to maintain constant arterial pH
Term
lateral spaces
Definition
gaps between adjacent cells in the tubule wall
Term
left atrial volume receptors
Definition
monitor the pressure of blood flwing through, which reflects the ECF volume; can moderately effect vasopressin release and thirst
Term
leptin
Definition
peptide secreted by adipose tissue. Leptin inhibits neuropeptide Y and is thought to be an appetite suppressant
Term
loop of Henle
Definition
segment of nephron's tubular component; sharp, U-shaped loop that dips into the renal medulla; has descending and ascending limbs; ascending passes through fork of afferent and efferent arterioles; after proximal tubule, before juxtaglomerular apparatus
Term
luminal membranes
Definition
membrane of tubule wall (one cell thick) that faces the tubular lumen
Term
lymph
Definition
fluid being returned from the interstitial fluid to the plasma by means of the lymphatic system where it is filtered through lymph nodes for immune defense
Term
macula densa cell input
Definition
1 of 3 inputs to RAAS; senstive to NaCl moving pas in tubular lumen; fall in NaCl --> increase renin secretion
Term
macula densa cells
Definition
specialized tubular cells in the juxtaglomerular apparatus region that detect changes in salt level of the fluid flowing past in the tubule; release adenosine; part of TGF
Term
medullary cardiovascular center
Definition
controls sympathetic and parasympathetic input to the heart; effected by the muscle chemoreceptors during exercise
Term
medullary countercurrent system
Definition
juxtamedullary nephrons long loops of Henle establish the vertical osmotic gradient; their vasa recta preserve this gradient while providing blood to the renal medulla; responsible for producing urine of varying concentrations
Term
mesangial cells
Definition
hold tufts of glomerular capillaries together; contain contractile elements; close off potion of the filtering capillaries upon sympathetic stimulation; reduces surface area for filtration --> decrease GFR
Term
metabolic H2O
Definition
byproduct produced by metabolic chemical reactions in cells that convert food and O2 into energy
Term
metabolic acidosis
Definition
characterized by reduction in plasam [HCO3-] caused by loss of [HCO3-] rich fluids or accumulation of non carbnoic acid acids; causes: severe diarrhea, diabetes mellitus, strenuous exericise; uremic acidosis
Term
metabolic alkalosis
Definition
reduction in plasma [H+] caused by a relative deficiency of noncarbonic acids, associate with increased HCO3-; causes: vomiting, ingestion of alkaline drugs
Term
micturition (urination)
Definition
process of bladder emptying; governed by micturition reflex and voluntary control
Term
micturition reflex
Definition
initiated when stretch receptor within bladder wall are stimulated; 250 to 400 mL before activated; afferent fibers --> spinal cord --> interneurons --> parasympathetic --> external sphincter opens --> urine expelled
Term
muscle hypertrophy
Definition
condition involving enlargement of muscles. May be induced pathologically or nonpathologically, as in weight training
Term
muscle pump
Definition
compression of veins by the contraction of skeletal muscles, forcing blood towards the heart against the flow of gravity; seen particularly in the deep veins of the lower limbs
Term
myogenic mechanism
Definition
property of vascular smooth muscle; arteriole smooth muscle inherently contracts in response to stretching and relaxes in response to decreased pressure; helps limit or enhance blood flow into the glomerulus despite changing blood pressure
Term
negative balance
Definition
losses for a substance exceed its gain; results in a decrease of the total body amount of that substance
Term
nephrons
Definition
functional unit of the kidney; smallest unit capable of forming urine
Term
net filtration pressure
Definition
net difference favoring filtration; average = 10mmHg; forces large volumes of fluid form the blood through the highly permeable glomerular membrane
Term
oral metering
Definition
regulation of oral input of substances
Term
osmolarity
Definition
measure of the concentration of the individual solute particles dissolved in a fluid
Term
osmotic diuresis
Definition
increased excretion of both water and solute caused by excess unreabsorbed solute in the tubular fluid
Term
output
Definition
excretion or metabolic consumption of a substance
Term
overhydration
Definition
excess free water
Term
pH
Definition
= log(1/[H+]); measure of the concentration of H+
Term
para-aminohippuric acid (PAH)
Definition
used to measure renal plasma flow; freely filterable and non reabsorbable
Term
passive reabsorption
Definition
all the steps in the transeptithelial transport of a substance from the tubular lumen to the plasma are passive
Term
pelvic diaphragm
Definition
skeletal muscle sheet that form the floor of the pelvis and helps support the pelvic organs; part of voluntary urination mechanism
Term
peritubular capillaries
Definition
subdivision of efferent arterioles which supply the renal tissue with blood and are important in exchanges between the tubular system and blood during conversion of the filtered fluid into urine
Term
plasma
Definition
fluid portion of the blood; makes up 1/5 of the ECF volume
Term
plasma clearance
Definition
volume of plasma completely cleared of that substance by the kidneys per minute; = urine concentration * urine flow rate / plasma concentration
Term
plasma-colloid osmotic pressur
Definition
caused by the unequal distribution of plasma proteins across the glomerular membrane; opposes glomerular filtration; average = 30mmHg
Term
podocytes
Definition
part of the inner layer of Bowman's capsule that are octopus-like cells that encircle the glomerular tuft
Term
positive balance
Definition
gains via input for a substance exceed its losses via output; results in an increase in the total amount of the substance in the body
Term
proximal tubule
Definition
segment of nephron's tubular component; lies entirely in the renal cortex; highly coiled; comes after Bowman's capsule and before loop of Henle
Term
reabsorption
Definition
flow of glomerular filtrate from the proximal tubule of the nephron into the peritubular capillaries
Term
renal atery and vein
Definition
enter and leave the kidney at the medial indentation
Term
renal cortex
Definition
outer region of kidney
Term
renal failure
Definition
functions of both kidneys are disrupted to the point that they cannot perform regulatory and exretory functions sufficiently to maintain homeostatis
Term
renal medulla
Definition
inner region of the kidney; made of renal pyramids
Term
renal pelvis
Definition
where urine drains after formation in kidneys, located at the medial inner core of each kidney
Term
renal pyramids
Definition
striated triangles in the renal medulla
Term
renal threshold
Definition
plasma concentration at which Tm of a substance is reached and substance first starts appearing in the urine
Term
renin
Definition
enzymatic hormone used in the RAAS; secreted by granular cells in juxtaglomerular apparatus
Term
renin-angiotensin-aldosterone system (RAAS)
Definition
hormal system involved in regulating Na+; granular cells of juxtaglomerular apparatus secrete renin to increase a fall in NaCl/ECF volume/blood pressure
Term
respiratory alkalosis
Definition
results of abnormal CO2 retention arising from hypoventilation that leads to elevated [H+]; causes: lung disease, despression of resp sys; nerve or muscle disorders affected resp sys.;or holding breath
Term
respiratory alkalosis
Definition
excessive loss of CO2 from the body as a results of hyperventilation that leads to too little [H+]; causes: fever, anxiety, and aspirin poisoning
Term
respiratory exchange ratio
Definition
ratio of the amount of carbon dioxide produced to the amount of oxygen consumed or taken up
Term
respiratory quotient
Definition
ratio of carbon dioxide produced by tissue metabolism to oxygen consumed in the same metabolism
Term
secondary active transport
Definition
no energy is "directly" used; specialized cotransport carriers located in proximal tubules transfer both Na+ and specifica organic molecule from the lumen into the cell; Na+ conc. gradient drives this, but it is made using Na+/K+ active pump
Term
secretion
Definition
release to a cell's exterior, on appropriate stimulation, of substances that have been produced by the cell
Term
sensible loss
Definition
loss of water of which a person is aware; sweating, feces, urine excretion
Term
sphincter
Definition
ring of muslce that, when contracted, closes off passage through an opening
Term
stable balance
Definition
total body input of a particular substance equals its total body output
Term
sympathetic input
Definition
1 of 3 inputs to RAAS; baroceptor reflex when blood pressure falls, that increases sympathetic activity to stimulate renin secretion
Term
thirst
Definition
sensation of dryness in the mouth and throat related to a need or desire to drink
Term
thirst center
Definition
part of brain that controls thirst
Term
training
Definition
generic term for deliberate goal-oriented practice, in a mental or physical activity, with the intent of bettering one's performance
Term
transcellular fluid
Definition
consists of a number of small specialized fluid volume, all of which are secreted by specific cells into a particular body cavity to perform some specialized function
Term
transepitheial transport
Definition
5 steps for substance to be reabsorbed tubular membrane to plasma: 1) cross luminal membrane, 2) pass through cytosol of tubular cell, 3) cross the basolateral membrane, 4) diffuse through interstitial fluid, 5) penetrate capillary wall to plasma
Term
tubular maximum (Tm)
Definition
upper limit on how much of a particular substance can be actively transported from the tubular fluid in a given period of time; all molecules have except Na+
Term
tubular reabsorption
Definition
as filtrate flows through the tubules, substance of value to the body are second renal process; returned to the peritubular capillary plasma; move from inside tubule (lumen) to the blood
Term
tubular secretion
Definition
third renal process; selective transfer of substances from the peritubular capillary blood into the tubular lumen; second route for subtsances to enter the renal tubules from blood;
Term
tubuloglomerular feedback (TGF)
Definition
involves juxtaglomerular apparatus; macula densa cells detect changes in the salt level of the fluid flowing past in tubule, more fluid passing raises salt delivery, macula densa cells release adenosine (local paracrine causes arteriole constriction) reducing GFR
Term
type A intercalated cells
Definition
secrete acid in form of H+ ions and reabsorbs bicarbonate
Term
type B intercalated cells
Definition
secrete bicarbonate and reabsorb H+
Term
urea
Definition
waste product from breakdown of protein; reabsorbed passively in proximal tubule
Term
uremia
Definition
urea in the blood indicates excess urea in the blood; renal failure common name
Term
uremic acidosis
Definition
sever renal failure; kidneys cannot rid body of even the normal amount of H+ generated, accumulates in body fluids and kidneys cannot conserve enough HCO3- to match
Term
ureter
Definition
smooth muscle-walled duct that exits at the medial border in close proximity to the renal atery and vein
Term
urethra
Definition
tube through which bladder empties urine to the outside; females = short and straight; males = long and follows curing course, dual function for urine and semen
Term
urinary bladder
Definition
temporarily stores urine; hollow, distensible, smooth muscle-walled sac
Term
urinary system
Definition
consists of urine forming organs: kidneys, structures that carry urine from kidneys to outside of body
Term
urine secretion
Definition
eliminatin os substances from teh body in the uren; results from the three renal processes
Term
vasa recta
Definition
blood vessel that has hairpin turn in the medulla and carries blood at a very slow rate, two factors crucial in the maintenance of countercurrent exchange that prevent washout of the concentration gradients established in the renal medulla
Term
vasopressin (antidiuretic hormone) (ADH)
Definition
increase the distal and collecting tubules permeability to water; produced in hypothalamus by the neuronal cell bodies; stored and released by the posterior pituitary gland; activates cAMP 2ndary messenger pathway and increases perimeability by promoting insertion of aquaporins into luminal membrane; increases H2O reabsorption from the filtrate; has graded response
Term
vassopressin (antidiuretic hormone)
Definition
increases permeability of the distal and collecting tubule to water and thus enhances water conservation
Term
vertical osmotic gradient
Definition
uniquely maintained in interstitial fluid of the kidney medulla; concentration of interstitial fluid progressively increases from the cotical boundary down through the renal medulla until it reaches 1200mosm/liter; enables kidneys to create urine of concentrations from 100-1200mosm/liter
Term
water diuresis
Definition
increased urinary output of water with little or no increase in exretion of solutes; rids body of excess water, compensation for ingesting too much water; excessive after alcohol because vasopressive is inhibited
Term
water intoxication
Definition
condition of overhydration, hypotonicity, and cellular swelling
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