CVPR Week 7: Hemodynamics Flashcards
1
Q
Objectives
A
2
Q
Question 1
A
D. Angiotensin
3
Q
Question 2
A
A. β adrenergic receptors
4
Q
Question 3
A
I think it is B but not 100%
5
Q
Identify
A
6
Q
Identify
A
7
Q
Identify
A
8
Q
Determinants of renal blood flow
A
9
Q
Renal blood flow % of CO
A
20%
10
Q
Pressure in renal arteries
A
11
Q
Renal capillaries properties
A
- Highly fenestrated capillaries have a high degree of permeability
- Two distinctly different capillary beds arranged in series
12
Q
Distinct capillary beds of the renal system
A
- Glomerular capillaries
- Peritubular capillaries
13
Q
Glomerular capillaries function
A
Filtration
14
Q
PEritubular capillaries function
A
Reabsorption
15
Q
Juxtoglomerular cells location
A
- Afferent arteriole
- abut closely to the distal tubule
16
Q
Identify
A
17
Q
Juxtaglomerular cells structure
A
Modified smooth muscle cells
18
Q
Juxtaglomerular cells function
A
Produce and secrete renin
19
Q
Identify
A
20
Q
Identify
A
21
Q
Vasa Recta Capillaries function
A
- Supply medullary blood flow
- maintain concentration gradient in the renal medulla
- Delivers nutrients
22
Q
Vasa Recta Capillaries location
A
Form long loops paralleling loops of Henle
23
Q
Identify
A
Vasa Recta Capillaries
24
Q
Vasa Recta Capillaries % of renal blood flow
A
10% of renal blood flow
25
Control mechanisms of renal blood flow
2 listed
* Intrarenal (Autoregulation)
* Extrarenal (extrinsic regulation)
26
Intrarenal regulation AKA
Autoregulation
27
Autoregulation of renal blood flow AKA
Intrarenal
28
Autoregulation of renal blood flow mechanisms and effects
* Myogenic tone
* Tubuloglomerular feedback
Maintain constant RBF & GFR almost constant when arterial pressure changes
29
Extrinsic regulation of renal blood flow AKA
Extrarenal
30
Extrarenal regulation of renal blood flow AKA
Extrinsic regulation
31
Extrinsic regulation of renal blood flow mediators & effects
* Sympathetic nerves
* Renin-angiotensin system
* Other hormone regulators
Regulate renal function to maintain whole body fluid homeostasis
32
Renal autoregulation
33
Myogenic tone
34
Myogenic tone is affected by?
* Myogenic tone is independent of extrarenal forces
* Stretch stimulates VSMC contraction
35
36
Identify
37
Identify
38
Identify
39
40
Role of the sympathetic nerves in renal extrinsic regulation
41
Vascular smooth muscle cells sympathetic receptors for renal vasculature
α adrenergic receptors
42
Identify
43
Juxtaglomerular cells sympathetic receptors
Juxtaglomerularcells contain β1 adrenergic receptors
44
sympathetic effects on juxtaglomerular cells
Stimulate renin release
Leads to formation of angiotensin II
45
Identify
46
Identify
47
Hypoxia activation of SNSA does what?
Affects renal function
48
Organ systems affected by SNSA
* Kidneys
* Vascular smooth muscle
* Endocrine
49
Kidney effects of SNSA
* Constricts afferent and efferent arterioles t decrease renal blood flow
* Potently increases Na+ reabsorption in the proximal tubule
* Large activation decreases GFR
50
Vascular smooth muscle effects on SNSA
* Constricts arteries to decrease renal blood flow
51
Endocrine effects of SNSA
Stimulates renin secretion (β1 receptors) to increase levels of angiotensin II and vasopressin
52
Describe the Renin-Angiotensin System
53
Effects of activating the Renin-Angiotensin system
5 listed
* Thrist
* Vasoconstriction
* Water reabsorption
* Sodium reabsorption
results in increased extracellular fluid volume
54
Summary of the Renin-Angiotensin system
55
Describe the juxtaglomerular apparatus
56
Mediators of the RAS
* SNSA
* Aldosterone
* ADH
57
SNSA AKA
Sympathetic nervous system activation
58
RAS AKA
Renin-Angiotensin System
59
Aldosterone effects on RAS
Aldosterone increases distal tubulue Na+ reabsorption
* Increases Na/K-ATPase activity in distal tubule basolateral membrane
* Increases lumiinal membrane Na+ and K+ permeability
60
ADH effects on the RAS
ADH causes water reabsorption
* Stimulates water reabsorption in the collecting duct
* Increases urea reabsorption in the collecting duct
61
Effects of Angiotensin on vascular smooth muscle
Causes constriction of arteries increasing peripheral resistance resulting in increased arterial blood pressure
62
Effects of Angiotensin on the central and peripheral nervous systems
Facilitate sympathetic transmission resulting in:
* constriction of arteries leading to increased peripheral resistance leading to increased arterial blood pressure
* increased cardiac output resulting in increased arterial blood pressure
63
Effects of Angiotensin on Adrenal cortex
increased aldosterone secretion leading to increased sodium reabsorption leading to increased sodium & water reabsorption leading to increased cardiac output resulting in increased arterial blood pressure
64
Effects of Angiotensin on direct effects on the kidneys on the tubules and arterioles
* increased sodium reabsorption and decreased GFR leading to sodium and water retention leading to increased cardiac output resulting in increased arterial blood pressure
65
Effects of Angiotensin on the brain
Causes increased thirst leading to increased water reabsorption and Increased ADH leading to increased water reabsorption causing sodium and water retention causing increased cardiac output resulting in increased arterial blood pressure
66
Angiotensin II effects on vascular smooth muscle
67
Angiotensin II effects on central and peripheral nervous systems
68
Angiotensin II effects on adrenal cortex
69
Angiotensin II effects on renal tubules and arterioles
70
Angiotensin II effects on the brain
71
Prostaglandins effect on renal blood flow
* Typically do not regulate renal blood flow or GFR under normal conditions (i.e. cyclo-oxygenase inhibition does not alter renal blood flow)
* Vasodilator PG's limit constriction of afferent arteriole
* PG-induced vasodilation maintains glomerular blood flow during volume or sodium depletion
* Cyclo-oxygenase inhibitors can cause acute renal failure during dehydration or following a stress such as surgery
72
Cyclo-oxygenase inhibitors and renal function
Acute renal failure during dehydration or following a stress such as surgery
73
Atrial natriuretic peptide is secreted from?
atria in response to stretch
74
Atrial natriuretic peptide effects on GFR
Dilates afferent arteriole and also constricts efferent arteriole to increase GFR
75
Atrial natriuretic peptide effects on urine production
Decreases Na reabsorption in medullary collecting to cause diuresis and natriuresis
76
Diuresis description
increased urine production
77
Natriuresis description
excretion of sodium in the urine
78
Brain natriuretic peptide secreted from
ventricles
79
Atrial natriuretic peptide and Brain natriuretic peptide levels in renal failure
increased levels in renal failure
80
ANP and BNP effects in renal failure
Increased levels in renal failure resulting in
* reduced renal clearance
* increased synthesis
