Physiology of Pregnancy: Schlabritz-Lutsevich Flashcards
What increases in CV during pregnancy?
BV
CO
SV
HR
What does not change in CV during pregnancy?
Veinous pressure
Mean arterial BP:
Although systolic and diastolic both go down
What goes down in CV during pregnancy?
TPR
Osmotic pressure
Hemoglobin
What is the name of the cells in the cytotrophoblast that cause drop from arterial to venous?
Extravillous trophoblast: invade spiral arteries of endometrium to form invasive cell columns
This drop in pressure keeps things from exploding… allows ex
What do decimalized cells look like at 4 weeks?
Large pale cells
What is the timeline of vascular remodeling?
4 weeks, it begins
5 weeks, heart beats for first time
What happens in vessel changes during remodeling?
Small size to large, high resistance to low resistance
0 Unmodified: 0 weeks 4 Vessel priming 8 Trophoblast invasion, loss of EC and VSMC 12 TC plugs dissolve 16 TC infiltration ceases 20 remodeling complete
When is local spiral artery remodeling complete?
20 wks
When is systemic artery remodeling complete?
24-28 weeks
What happens to arteries in pregnancy?
Less resistance, (maybe larger diameters?)
The remodeling of the spiral done when? systemic?
20-spiral
24-28-systemic
What happens to TPR in gestation at 5 weeks?
20-25% deducting by 5 weeks
What is the reduced TVR due to?
Reduced vasomotor tone
Remodelling of resistant size arteries (MMP9/3)
What are changes in vessels due to, broadly?
Angiogenic and antigenic factor balance
What placental growth factor a analogue for?
VEGF: angiogenesis
What percent of maternal blood goes to fetus eventually?
35%
If we have imbalance in angiogenic/antiangiogenic factors, what happens?
Pre-ecclampsia
Remember what anti-angiogenic factors?
Soluble VEGF-Receptor 1
S-Fleet
TPR is decreased due to what?
NO
PGI2 from COX1 and 2
cGMP (decreases Ca+2)
What is emphasized as important to keep vessel relaxed and TPR low?
cGMP
What is cause of relaxation in regard to K channels?
Hyperpolarization
Placental casues and increase in?
ATII??
What is increased compliance?
distensibility (by blood volume)
What does increased compliance do to after load of heart?
Decreased after load
What happens first, increased BV or decreased TPR?
We don’t know… she thinks vascular remodeling
What is an important mechanism to allow fetal growth?
Increased plasma volume, erythrocyte volume
What happens to the HCT in pregnancy?
Decreases
Does erythrogenesis match plasma volume increase?
No, thus HCT is low
When does BV return to normal after delivery?
by 6 weeks
What happens to heart chambers in pregnancy?
Left ventricular hypertrophy (same as athletes!)
What is the difference between the physiological and pathological heart hypertrophy?
Fibrosis and elasticity!
Patho: fibroblasts increase, walls thicken too much
Phys: myocytes increase, walls proportionate thick
What increases with heart wall stretching?
ANP
BNP
cGMP**emphacized
*feedback to decrease BP in kidneys and adrenals
What is the role of microRNA?
MiR208 is heart specific microRNA
Animals treated with miR208 are resistant to what?
high fat diet
What does miR208 inhibit?
MED13, an inhibitor of mediators of fat storage
Deletion of MED13 causes what?
Obesity
How does the heart regulate fat storage?
Thorugh miR208 and MED13
What are the changes in kidney in pregnancy?
GFR increases up to 50%
What happens to creatinine in pregnancy?
0.4 mg/dl increase on average (0.9 to 1.3)
What happens to the collecting system of the kidneys?
physiological hydronephrosis due to increased progesterone relaxation of ureters and fetal compression
Which side has more hydronephrosis in pregnant kidneys?
Right side
What is the respiratory changes in pregnancy?
Diaphragm elevation
widened rib cage (2cm diameter, 6 cm circumference)
Bigger chest (5-7cm)
Subcostal angle from 68 to 103 degrees
Is respiratory muscle function effected by pregnancy?
NO! no change in reap. muscles
What happens to abdominal muslces in pregnancy?
Less tone
Less active
Respiration is diaphragmatic
What is the change in the subcostal angel?
68 to 103 degrees
What is the change in tidal volume?
increase 35-50%
What is the change in total lung capacity?
4-5% reduction by elevation of diaphragm
What happens to functional residual capacity, residual volume, respiratory reserve volume?
Decrease about 20%
What causes increase in alveolar ventilation in pregnancy?
Larger tidal volume
Smaller residual volume
What happens to inspiratory capacity?
increase 5-10%
What percent of oxygen is taken by placenta?
40%!!!
Vital capacity is what?
Almost the SAME
Overall what happens in respiratory pregnancy?
More efficient gas exchange
What are the increases in hormones in pregnancy?
Increase: Estrogen/Progesterone Ratio Prolactin Placental GH TNF-a Leptin Free cortisol
What are the decreases in hormones in pregnancy?
Decrease:
Pituitary GH
Adiponectin
What do the changes in hormones in pregnancy compare to?
Obesity! We need to deposit fat… insulin resistance and available glucose.
Our babies are what?
Fat!
What hormonal adaptations lead to fat babies?
Increased TNF-a
Leptin
Cortisol
Deacrease Adiponectin
Majority of Leptin comes from where in pregnancy?
Placenta! 10 fold increase
What is the pregnancy response to leptin?
Leptin resistant state, like obesity
What is the overview of gut micro biome and metabolic change in pregnancy?
Weight gain
Insulin desensitization
Altered microbiota: transplant makes fatter mouse
What happens to fat in pregnancy?
Shunt to fetus?
What acts as a barrier to active glucocorticoids (cortisol) in placenta?What does it do to them?
11 beta hydroxysteroid dehydrogenase type 2 in placenta
Converst to cotisone
What happens if 11 BHSD2 is low in placenta?
Cortisol gets across
Growth retardation
What deactivates cortisol in placenta?
11bHSD2
What can happen to molecules from mother in placenta?
Metabolism
Transport
No transport
What protects barrier of blood-blood barrier placenta?
Syncytiotrophoblast:
Vasculosyncyntial membrane
What GLUT gets glucose in in placenta?
GLUT 1
What may interfere with amino acid transport in placenta?
Glucose
Lipid metabolism
What type of fats does placenta prefer?
Long chaing polyunsaturated fatty acids (LC-PUFAs)
Building blocks for fetal brain
(cholesterol not quite known yet)