Pbd Renal

Front 1

T/F?
Dietary sodium restriction can result in an upregulation of the inducible Cox 2 expression and the resulting release of renin.

Back 1

True

Front 2

T/F?
In addition to ACE another enzyme that can convert Angtiotensin I to Angiotensin II in man is the chymase enzyme

Back 2

True

Front 3

T/F?
Angiotensin II is important in the clotting system. It can inhibit the production of plasmin via its activation of a plasminogen activator inhibitor

Back 3

True

Front 4

The kidney is important in volume and blood pressure control. It has a powerful negative feedback on pressure and the process by which the kidney performs this feet is called __________.

Back 4

Pressure Diuresis

Front 5

In the two kidney, one-clip model of hypertension renin levels are initially elevated. Do they stay elevated or come back down to normal?
Yes (stay elevated).
or No (return towards normal).

Back 5

Yes

Front 6

T/F?
Dietary sodium restriction can result in an upregulation of the inducible Cox 2 expression and the inhibition of renin release.

Back 6

False
(stimulates renin release)

Front 7

T/F?
The kidneys play an important role in the degradation of the active form of Vitamin D to the inactive form

Back 7

False

Front 8

T/F?
Specialized epithelial cells of the ascending limb of the renal tubule, referred to collectively as the macula densa, produce and store renin in granules

Back 8

False

Front 9

T/F?
Autoregulation, via the myogenic mechanism, can regulate renal blood flow and, therefore, glomerular filtration rate (GFR), even under extreme conditions such as hemorrhage resulting in serious hypotension

Back 9

False

Front 10

The hormone produced by the kidneys that stimulates bone marrow production of erythrocytes is ___________.

Back 10

erythropoietin

Front 11

The specialized epithelial cells that make up the visceral layer of Bowman's Capsule are referred to as ___________ (name of cell).

Back 11

podocytes

Front 12

______________ cells, found in association with the glomerulus, are phagocytic, have myofilaments, and lay down an extracellular matrix that supports the glomerular capillaries.

Back 12

Mesangial

Front 13

T/F?
Angiotensin converting enzyme (ACE) cleaves angiotensin I (AI) to form angiotensin II (AII).

Back 13

True

Front 14

T/F?
Secretion by the renal tubules represents a second pathway for substances carried in the plasma to enter the tubules.

Back 14

True

Front 15

T/F?
The macula densa consists of specialized vascular cells in the afferent and efferent arterioles that produce and store renin.

Back 15

False
(it's in the distal tubule adjacent to the afferent arteriole & JG cells)

Front 16

Low sodium level is the signal that initiates a series of steps that ultimately _______________ renin release.

Back 16

stimulates

Front 17

The renin-angiotensin system (RAS) is intimately involved in a variety of physiological functions. It's major effect is what?

Back 17

maintains BP, salt & H2O balance

Front 18

The RAS has many other actions (besides maintaining BP, salt & H2O balance) ranging from ____________ of vessels to a role in ___________.

Back 18

vasoconstriction
inflammation

Front 19

The RAS is composed of a _____________ (vascular) and ___________tissue system

Back 19

systemic
local

Front 20

The RAS is involved in _____ & _____ ____ regulation of blood pressure

Back 20

short & long term

Front 21

What is the only precursor protein for the family of angiotensin peptides that's the rate-limiting factor in the activity of the systemic renin angiotensin system?

Back 21

Angiotensinogen

Front 22

_____________ is synthesized in a number of cells/tissues, primarily from the ___________ for the systemic derived RAS.

Back 22

Angiotensinogen

hepatocytes

note: This pro-hormone is also synthesized in the CNS, heart, vasculature, kidney, and adipocyte (fat cell).

Front 23

T/F? In hapatocytes, pre-pro-angiotensinogen is processed and constitutively stored.

Back 23

False

(it's secreted!)

Front 24

Angiotensinogen is regulated by other __________ components.

Back 24

endocrine

Front 25

In _____a_______ angiotensinogen mRNA is upregulated by _____a_________.

In the ____b_____ (name other) angiotensinogen mRNA is upregulated by _____b_____.

Back 25

a) adipose tissue, insulin

b) hepatocyte, estrogen

Front 26

Angiotensinogen is cleaved by the enzyme ___a_____ to form the N-terminal decapeptide ____b_____, which occurs in the circulation.

Back 26

a) renin

b) AngI

Front 27

_______ (name the 5 things) exert transcriptional control via specific regulatory DNA sequences of the angiotensinogen gene.

Back 27

glucocorticoids
estrogen
thyroid hormone
insulin
& selected cytokines

Front 28

Synthesis of angiotensinogen can be stimulated by _______ & __________.

Back 28

inflammation & Angiotensin II

Front 29

In the synthesis of angiotensinogen, Ang II may exert a _______ feedback regulation via a(n) _______.

Back 29

positive

AT1 receptor

Front 30

Several lines of investigation suggest that angiotensinogen contributes to the __________ phenotype.

Back 30

hypertensive

Front 31

Polymorphisms within the angiotensinogen gene have been genetically linked with ___________ ___________.

Back 31

familial hypertension

Front 32

Angiotensinogen is the protein from which angiotensins are formed by _________ _______reactions.

Back 32

proteolytic cleavage

Front 33

T/F?
Angiotensinogen levels in the plasma affect BP.

Back 33

True

Front 34

What is the highly substrate-and species-specific aspartyl protease enzyme of the RAS?

Back 34

renin

Front 35

T/F? Renin catalyzes the rate limiting-step in a cascade that results in the formation of angiotensin I and its congeners.

Back 35

False
(formation of angiotensin II)

Front 36

After renin catalyzes the rate limiting-step for formation of angiotensin II, ___ (#) aa Angiotensinogen change to a __ (#) aa Angiotensin I.

Back 36

14 --> 10

Front 37

The _________ (name cell) are the systemic source for renin synthesis, storage and release.

Back 37

juxtaglomerular (JG) cells

Front 38

Initial step in synthesis of renin in the JG cells is the formation of the ___________ by renin _____.

Back 38

pre-pro-renin

mRNA

Front 39

In the JG cells, after the initial step of renin synthesis, the ___(#) aa "pre" sequence is cleaved, leaving pro-renin that is deposited into ________.

Back 39

23

granules

Front 40

In the ______ the 43 aa "pro" sequence is cleaved to the active _____ (#)Dalton renin molecule.

Back 40

golgi

40,000

Front 41

This cleavage and activation of renin is mediated by the enzyme - _______________.

Back 41

cathepsin B

Front 42

After cleavage & activation of renin by _____a______, the renin storage granules migrate to the cellular surface where the release the active enzyme through ____b_____ into the blood (vascular lumen), where there is a ____c______ release of renin.

Back 42

a) cathepsin B

b) exocytosis

c) constitiutive or basal

Front 43

Secretion of renin from the JG cells is controlled predominately by 3 pathways; 2 are ___a___ and 1 is through the ____b______.

c) What are the 2 from (a)?
d) What is the 1 from (b)?

Back 43

a)local within the kidney

b)nervous system

c)Macula densa pathway &
Intrarenal baroreceptor pathway

d) Beta-Adrenergic receptor pathway

Front 44

The __a_____ is a modified plaque of cells in the __b____ tubule of the nephron, located at the end of the loop of Henle and adjacent to the ___c_____ arteriole and the ___d____.

These components make up the _____e_____.

Back 44

a) macula densa

b)distal

c) afferent

d) JG cells

e) JG apparatus

Front 45

The JG apparatus monitors _____ levels.
Low levels initiate a series of steps that ultimately _______ renin release.

Back 45

Na+

stimulates

Note: This is likely a more CHRONIC adaptive system for regulating renin release.

Front 46

T/F? Substances implicated in the feedback signal for renin release are PGE2 and Cox 1 enzyme.

Back 46

False
(PGE2 & Cox II enzyme!)

Front 47

PGE2 & CoxII enzymes __________ renin release.

Back 47

stimulate

Front 48

Dietary sodium restriction results in an upregulation of the inducible ________ expression.

_______ is a substance that ___________ renin release.

Back 48

CoxII

Adenosine, inhibits

Front 49

The second intrarenal mechanism (next to the macula densa pathway) is called the ________________ pathway

Back 49

intrarenal baroreceptor
pathway

Front 50

The renal baroreceptor is an interrenal vascular receptor in the afferent arteriole that ________________ renin secretion in response to ______________ renal perfusion pressure and attenuates renin secretion as renal perfusion is _________.

Back 50

stimulates

reduced

elevated

Note: this (BP) is the most powerful regulator of renin release.

Front 51

The third mechanism regulating renin secretion (besides the macula densa & intrarenal baroreceptor pathway) is the ____________ pathway

Back 51

beta-adrenergic receptor

Front 52

T/F? The JG cells are directly innervated by the parasympathetic nerves.

Back 52

False
(sympathetic nerves)

Front 53

Direct stimulation of the JG cell nerves (in the beta-adrenergic receptor) will ____________ renin release.

This is an acute pathway by which ________ activation of the RAS is provoked by such stimuli as _____________.

Back 53

increase

rapid

stress and posture

Front 54

T/F?
The three regulatory pathways for renin release are embedded in a physiological network, which is a short-loop positive feedback system.
(as well as a long-loop)

Back 54

negative

Front 55

T/F? Increases in renin secretion will result in a decrease in Ang II. (part of short-loop neg. fb)

Back 55

false (increases AngII)

Front 56

Ang II in turn stimulates _____ on the JG cells to ________ renin release (part of short-loop neg. fb)

Back 56

AT1R

inhibit

Front 57

Ang II increases BP via ____ and the increase in BP _________ renin release. This is part of which feedback?

Back 57

AT1R

inhibits

part of the long-loop neg. fb

Front 58

On of the humoral factors involved in renin release is the primary second messenger _____ (for beta-adrenergic and PGE). Is this stimulatory or inhibitory? What's a 2nd msger?

Back 58

cAMP

stimulatory

cGMP

Front 59

Renin release is inhibited by an increase in intracellular _______.

Back 59

calcium

Front 60

Factors that stimulate cGMP such as ____ would ____ renin release.

Back 60

ANP

inhibit