DSA Flashcards
How do you denote out of capillary movement or into capillary movement
Filtration is out of capillary and is a positive numer; move into capillary is absorption and a negative
What is a pressure formula for CO
CO= (Pa-Pv)/TPR
Systemic circulation is model through what type of resistance
Parallel
Reynolds number greater than what gives turbulent flow
2000; Nr=densitydiametervelocity/viscosity
What does turbulent flow lead to
Sounds (bruits) and lesions (arteriosclerosis)
What is a common increase in pulse pressure; decrease
Arteriosclerosis; aortic stenosis
How do we estimate LA pressure
Pulmonary wedge pressure
What causes active hyperemia
Increases in CO2, H+, K+, lactate, or adenosine
Decreases in O2
Shear is related to the release of what
NO
What are our main vasodilators
Histamine and bradykinin
What does serotonin cause
Vasoconstriction in response to tissue damage
What systems are largely under metabolic control
Brain and coronary
What parasympathetic receptor decreases heart rate? Sympathetic that increases it
M2; β1
Increased stretch causes an increase/decrease in baroreceptors
Increase
Where is renin secreted from in response to what change in BP
Kidney; drop in BP
Where is aldosterone secreted from
Adrenal cortex
What does angiotensin II bind to
AT1 channels
What do natriuretic peptides do
Arterial dilation - decreases TPR
Increases fluid loss - decreases preload
Inhibits renin - decreases both TPR and preload
What is the cushing reflex
Hypertension, bradycardia, irregular respiration
What are multiunit SM? Where are they found
SM that are individually innervated; ciliary muscles of eye, iris, and piloerector muscles
What are unitary SM? Where are they found?
They are SM that allow them to contract together (in unison)
GI tract, bile ducts, uterus
SM are slower/faster than skeletal muscles
Slower; they use the latch mechanism
Do SM generate more/less force than skeletal muscles
More force because cross bridges are up longer
Where does SM bind calcium during contraction
Calmodulin
What does calmodulin activate
Myosin light chain kinase
What functions to stop SM contraction
Myosin light chain phosphatase
What portion of neurons innervate SM
Varicosities; they are bulge sites
What do platelets secrete that we care about
thromboxane A2 and 5HT (serotonin)
These are vasocontrictors
What chemicals relate to the vasospasm
Thromboxane A2 and serotonin
How do we form a platelet plug
Activate vWF that initiates binding of collagen to platelets
binding of platelet receptor to collagen
What happens during platelet activation
Platelet swells, extends podocytes, contracts, and secretes thromboxane A2 and ADP
What causes blood coagulation
Activation of thrombin - which generates fibrin and fibrin polymerizes
Prothrombin activator activates thrombin
What causes clot retraction (contraction)
Fibrin stabilizing factor
It also requires calcium ions
What causes repair of vessel wall damage
Platelet-derived GF
What is responsible for the lysis of clots
Plasmin which must be activated from plasminogen
t-PA inhibitor normally doesn’t allow this but thrombin activates protein C which inactivates t-PA inhibitor
What are some clot inhibitors
Fibrin - inhibits thrombin
Prostacyclin - made by injured endothelial cells, vasodilation, limits platelet aggregation
Antithrombin III - when bound to thrombin it is an anticoagulant
Heparin - derived from mast cells, increases antithrombin efficacy
What factors require Vit K
II, VII, IX, X
What does Factor VII’s half life
4-6 h
What does PT measure
Extrinsic pathway
What does PTT measure
Intrinsic pathway
What is primary hemostasis? Secondary?
Initial formation of a clot; reinforcement of the clot
How does Warfarin work
Decreasing activity of Vit K dependent epoxide reductase
Vit K is a cofactor in synthesizing factors
II, VII, IX, X, Protein S and C
What deficiency causes an increased risk of venous thrombosus
Protein C
What is hemophilia A
Defect in intrinsic pathway (Factor 8)
What can we use to make Glycerol 3 P
DHAP via glycolsis
And glycerol kinase (which fat doesn’t have)
What enzyme do intestinal cells use to make fat
Fatty acyl coa synthetase
What increases hormone sensitive lipase activity? Decreases
Glucagon, epinephrine, norepinephrine
Insulin
What is the MoA of hormone sensitive lipase
GPCR -> AC ->PKA
Niacin can be used to help do what
Decrease LDL and increase HDL
What is type I hyperlipoproteinemia
Familial hyperchylomicronemia (increase in chylomicrons and triacylglycerol)
What is type 2a/b
Familial hypercholesterolemia
Cholesterol increased
Triacylglycerol increased
LDL increased
VLDL increased
What is the MoA of Type II hyperlipoproteinemia
Defects in uptake of LDL via LDL receptor
This causes increased cholesterol in blood and subsequent atherosclerosis
