hormones

Question 1

most of the hormones made by the placenta are made by

Answer 1

syncytiotrophoblast

Question 2

name the hormones made by the syncytiotrophoblast

Answer 2

1. hCG
2. hPL (placental lactagen)
3. placental GH
4. leptin
5. PAPP-A
6. progesterone
7. oestrogens

Question 3

hCG function

Answer 3

maternal recognition of pregnancy (acts on LH > maintain corpus luteum > maintain uterine lining)

Question 4

hPL function

Answer 4

stimulates maternal appetite, lipolysis & FFA levels (induces growth & differentiation of mammary gland tissue)

Question 5

placental GH function

Answer 5

stimulates growth, maternal lipolysis and gluconeogenesis by regulating maternal IGF1 levels and insulin sensitivity

Question 6

leptin function

Answer 6

• prevents uterine contractions
• upregulated placenta transporters
  (mother is leptin resistant to lay down adipose reserves)

Question 7

pregnancy associated protein A (PAPP-A) function

Answer 7

fetal growth promoting as it cleaves IGFBPs to enhance their bioavailability

Question 8

progesterone function

Answer 8

• maintains uterine lining
• stimulates endometrial gland activity
• appetite stimulant?

Question 9

oestrogen function

Answer 9

maintenance of pregnancy

Question 10

how are female fetuses protected from masculinisation

Answer 10

• cholesterol taken up by the placenta > pregnenolone
• fetal adrenal + liver will sulphinate it to inactivate it
• steroid derivatives transported back into placenta, which convert into androgens & oestrogens > secreted back into maternal circulation