Blood flow regulation

Question 1

which hormones are involved in increasing blood flow

Answer 1

adrenaline
angiotensin 2

Question 2

adrenaline

Answer 2

sympathetic stimulation
secreted by adrenal gland
binds to alpha 1 adrenergic receptors on afferent and efferent arterioels
contraction of smooth muscle cells
constriction
low renal blood flow

Question 3

angiotensin 2

Answer 3

endothelial cells surrounding blood vessels
respond to low blood pressure
final product in RAAS
travels through blod
binds to receptors on afferent and efferent
cause constriction
low renal blood flow

Question 4

angiotensin 2 maintaining GFR

Answer 4

efferent mroe receptive to angiotensin 2 than the afferent
low angiotensin 2 only the efferent will constrict
more blood remains in glomerulus
GFr preserved
in high levels then decreased renal blood flow and GFR

Question 5

what is involved in decreasing blood flow

Answer 5

atrial natriuretic peptide
brain natriuretic peptide

Question 6

brain natriuretic peptide location

Answer 6

ventricles of heart

Question 7

atrial natriuretic peptide

Answer 7

atria of hwart

Question 8

natriureitc peptide function

Answer 8

secreted when cardiac workload and walls of atria and ventricles are stretched
bind to natriureitc peptide recpetors on smooth muscles
dilation of afferent
constriction of efferent
increases renal blood flow
prostaglandin and dopamine

Question 9

prostaglandin

Answer 9

E2 and I2
produced in kidney with sympathetic stimulation
dilation of afferent and constriction of efferent
increases renal blood flow
even in fight or flight

Question 10

dopamine

Answer 10

made in the brain and kidneys
brain is neurotransmitter
binds to dopaminergic receptors on smooth muscle cells
constrcits capillaries in skin and muscle
dilatation in heart and kidney
afferent and efferent dilated
low dopamine concentrations will increase rneal blood flow

Question 11

autoregulation

Answer 11

local mechanisms in the kidney which keep renal blood flow and GFR constant over range of systemic blood pressure, kidney adjusts own arteriolar resistance

Question 12

blood pressures and optimum for kidney

Answer 12

Systolic blood pressure less than 80 then renal blood flow low
Systolic reaches 80 then the smooth muscle cells in the arteriolar wall are relaxed as this is optimum
80-200 the smooth muscles more constricted
above 200 blood flow increases the same rate as blood pressure

Question 13

2 mechanisms of kidney autoregulation

Answer 13

myogenic
tubularglomerular

Question 14

myogenic

Answer 14

smooth muscle reflex
when stretched they will contract
more stretch more likely to contract
constriction of afferent and efferent

Question 15

tubularglomerular

Answer 15

macula densa chemoreceptor
detects increase in GFR due to the sodium and chloride ion concentration
blood pressure rises
renal blood flow rises
GFR rises
more fluid
more NaCl reaching the macula densa
macula densa release adenosine
diffuses to juxtaglomerula cells
increases arteriolar resistance
decreases GFR