Gfr, Transportation, Reabsorption

Front 1

net filtration rate (NRT)

Back 1

blood hydostatic pressures- colloid osmotic pressure - capsular hydrostatic pressure

(~ 10mm Hg)

Front 2

decrease in blood pressure

Back 2

decrease glomerular hydrostatic pressure and GFR

Front 3

homeostatic mechanism for blood pressure

Back 3

arteries of the body at balloons...when containing less fluid, the pressure is lower...decreased GFR and urine output will prevent further fluid loss and catastrophic loss of blood pressure

Front 4

renal autoregulation of GFR

Back 4

helps ensure that wastes are removed despite variation in blood pressure...keeps GFR relatively constant in face of small changes in MAP

Front 5

afferent arterioles and autoregulation

Back 5

respond to changes in blood pressure to control GFR

Front 6

arterial pressure increases

Back 6

afferent arterioles constrict to reduce GFR

Front 7

arterial pressure decreases

Back 7

afferent arterioles relax to increase GFR

Front 8

vasocontriction

Back 8

decrease blood flow into glomerulus

Front 9

vasodilation

Back 9

increases blood flow into the glomerulus

Front 10

myogenic response (renal autoregulation)

Back 10

1. all stretched arteries constrict in response to strech
2. when afferent arterioles are stretched from increased MAP -> they constrict to reduce GFR

Front 11

tubuloglomerular feedback

Back 11

1. local sensors that assess flow of fluid through the tubules
2.if flow is too low, changes are made to increase flow and vice versa.
3. sensors are in the macula densa cells of the distal tubule

Front 12

macula densa cells

Back 12

regulate vasoconstriction/dilation of special cells in the afferent arteriole called JUXTAGLOMERULAR cells

Front 13

if flow is too low, macula densa cells...

Back 13

release nitric oxide to cause afferent arteriole dilation

Front 14

if flow is too high, macula densa cells...

Back 14

release ATP and prostaglandins, which cause juxtaglomerular cell constriction

Front 15

sympathetic nervous system regulation of GFR

Back 15

1. stimulated during exercise or blood loss
2. causes constriction of afferent arterioles
3. decreases GFR

Front 16

exercise

Back 16

reduction of GFR diverts blood from kidneys to working muscles

Front 17

blood loss

Back 17

reduces filtration to keep blood volume up

Front 18

hormonal regulation of GFR

Back 18

1. epinephrine is secreted by the adrenal medulla in response to stress, exercise, or blood loss
2. epinephrine binds to G-protein link receptos in the afferent arteriole -> vasoconstriction of the arteriole and decreased GFR

Front 19

hormone released from the heart in response to high blood pressure

Back 19

atrial natriuretic hormone
-increases GFR by vasodilating afferent arterioles and constricting the efferent arteriole

Front 20

if a drug raises levels of prostoglandins around the juxtaglomerular cells it will...

Back 20

decrease GFR

Front 21

blocking a pathway that causes a function to increase it'll...

Back 21

cause a decrease

Front 22

drugs that block the sympathetic nervous system

Back 22

decrease heart rate

Front 23

drugs that block the parasympathetic nervous system

Back 23

increases heart rate

Front 24

how do ions like Na+ move through a lipid bilayer?

Back 24

A channel

Front 25

how do polar organic molecules like glucose and amino acids move through the cell membrane?

Back 25

transporter

Front 26

channel

Back 26

: membrane protein that allows high rates of movement of an ion through a hole. It does not saturate, and the higher the electrochemical gradient the faster the transport

Front 27

transporter

Back 27

membrane protein with binding sites for molecules that flip over in response to the electrochemical gradient for all binding molecules. They saturate because at some point all binding sites are filled.

Front 28

passive transport

Back 28

movement of a molecule down an electrochemical gradient

Front 29

active transport

Back 29

movement of a molecule against an electrochemical gradient, powered by energy from the cell (ATP)

Front 30

NaCl and water reabsorption

Back 30

1. Na+/K+ ATPase are located on the basolateral side and pumps Na+ to ECF, Na+ is absorbed into blood
2. Na+ is absorbed across apical membrane
3. Cl- moves between cells due to electrical gradient across epithelia
4. water follows salt between cells because of osmotic gradient
5. water crosses the membranes through aquaporins.

Front 31

transport of water driven by Na+ transport

Back 31

1. Na+ is pumped out by Na+/K+ pump using active transport
2. produces low Na+ concentration inside the cell
3. Na+ diffuses from filtrate into cell through Na+ channels in luminal side
4. K+ diffuses out of channels in basolateral side of cell and is recycled
5. water follows salt

Front 32

paracellular transport

Back 32

important for reabsorption of salts, water and nutrients in the proximal tubule