long term control of blood pressure

Question 1

is long term control of blood pressure mediated by arterial baroreflex?

Answer 1

no

Question 2

where does the long term control of blood pressure revolve around?

Answer 2

around the control of plasma volume by the kidneys

Question 3

what three hormone systems does long term control of blood pressure?

Answer 3

Renin-angiotensin-aldosterone system
Antidiuretic factor (ADH, vasopressin)
Atrial natriuretic peptide

Question 4

whats the function of the kidney?

Answer 4

Excretion of waste products 
Maintenance of ion balance
Regulation of pH 
Regulation of osmolarity 
Regulation of plasma volume

Question 5

what regulates plasma volume?

Answer 5

kidney

Question 6

does renal counter current system create a high or low osmolarity outside the collecting duct?

Answer 6

high

Question 7

what determines how big the osmotic gradient is?

Answer 7

control of Na transport

Question 8

what does control over the permeability of the collecting duct to water determine?

Answer 8

determines if water follows that osmotic gradient or not

Question 9

can you control how much water is lost in the urine and how much is retained?

Answer 9

yes

Question 10

what effect will making the collecting duct very permeable to water do?

Answer 10

result in lots of water reabsorption, little urine, and conserve plasma volume

Question 11

what effect will making the collecting duct very impermeable to water?

Answer 11

result in little reabsorption, lots of urine (= diuresis), and a reduction in plasma volume

Question 12

will a permeable collecting duct result in small or large volume of hyper or hypo osmotic urine?

Answer 12

small volume of hyper osmotic urine

Question 13

will a impermeable collecting duct result in small or large volume of hyper or hypo osmotic urine?

Answer 13

large volume of hypo osmotic

Question 14

where is renin produced?

Answer 14

From the juxtaglomerular (= granule cells) of the kidney

Question 15

what triggers renin production?

Answer 15

Activation of sympathetic nerves to the juxtaglomerular apparatus
Decreased distension of afferent arterioles (the “renal baroreflex”)
Decreased delivery of Na+/Cl- through the tubule

Question 16

what are all signs of low MAP

Answer 16

Activation of sympathetic nerves to the juxtaglomerular apparatus
Decreased distension of afferent arterioles (the “renal baroreflex”)
Decreased delivery of Na+/Cl- through the tubule

Question 17

what does renin do?

Answer 17

Converts inactive angiotensinogen to angiotensin I

Which is in turn converted by angiotensin converting enzyme to angiotensin II

Question 18

what does angiotensin II do?

Answer 18

Stimulates release of aldosterone from the adrenal cortex
Increases release of ADH from the pituitary
Is a vasoconstrictor

Question 19

whats the effect of Stimulates release of aldosterone from the adrenal cortex

Answer 19

Increases Na+ reabsorption in the loop of Henle

Therefore reduces diuresis and increases plasma volume

Question 20

whats the effect of Increased release of ADH from the pituitary

Answer 20

Increases water permeability of the collecting duct
Therefore reduces diuresis and increases plasma volume
And increases sense of thirst

Question 21

whats the effect of vasoconstriction on TPR

Answer 21

increases

Question 22

can you say that Renin-angiotensin-aldosterone system is a negative feedback system?

Answer 22

yes
Multiple mechanism detect any decrease in MAP
Stimulates release of renin
This evokes multiple mechanisms which increase MAP

Question 23

where is antidiuretic produced?

Answer 23

Synthesised in the hypothalamus

Released from the posterior pituitary

Question 24

what triggers ADH release?

Answer 24

A decrease in blood volume

An increase in osmolarity of interstitial fluid

Circulating angiotensin II

Question 25

what does ADH do?

Answer 25

``` Increases the permeability of the collecting duct to H2O, therefore reduces diuresis and increases plasma volume Causes vasoconstriction (hence its alternative name, vasopressin), therefore increasing MAP ```

Question 26

can you say that ADH is a negative feedback system?

Answer 26

yes Multiple mechanism detect any decrease in MAP Stimulates release of ADH This evokes multiple mechanisms which increase MAP

Question 27

where is atrial natriuretic peptide produced?

Answer 27

Produced in, and released from myocardial cells in the atria

Question 28

what triggers ANP release?

Answer 28

Increased distension of the atrium

Question 29

what does ANP do?

Answer 29

Increases excretion of Na+ (natriuresis) Inhibits the release of renin Acts on medullary CV centres to reduce MAP

Question 30

can you say that ANP is a negative feedback system?

Answer 30

yes