Transcript Perineum - UMS Student Government

PREGNANCY PROTEINS
• Early pregnancy factor (EPF)
• Placental proteins:
– pituitary-like hormones: hCG, hPL, ACTH, hCT
– hypothalamic-like hormones: GnRH, CRH, TRH,
SRIF
– growth factors: inhibin, activin, IGFs, EGF
– other peptides: SP-1, PAPP-A, PP-5
• Decidual proteins: PRL, relaxin, IGFBP, PP-14
• Fetal proteins: AFP
HUMAN PLACENTA
Early pregnancy factor (EPF)
• immunosupressive protein produced by
maternal ovaries stimulated by PAF
• earliest known indicator of fertilization (48hr)
• maximum production 0- 4 weeks then 
• function:
– prevents rejection of an embryo (binds to
lymphocytes)
– growth factor (?)
• clinical applications : to be evaluated
HUMAN CHORIONIC GONADOTROPIN (hCG)
• glycoprotein hormone, two chains
– alpha-subunit (chromosome 6) : identical
– beta-subunit (chromosome 19) : unique
activity and specificity
• trophoblastic tissue (syncytiotrophoblast)
– normal placenta (also multiple placenta)
– gestational trophoblastic disease (hydatiform
mole and choriocarcinoma;  x 3-100)
– ectopic pregnancy
hCG levels during pregnancy
HUMAN CHORIONIC GONADOTROPIN (hCG)
• control of secretion: placental GnRH secreted
by cytotrophoblast ( activin,  inhibin)
• normal pattern of secretion :
–  8 days post conception, dbl time 2-3 days
– peak value 8-10 wk. of gestation ( 120,000 IU/L)
–  and reach plateau  20,000 IU/L at 18-20 wk. of
gestation
–  in multiple pregnancy
– at 1,000-1,500 IU/L intrauterine gestation visible
with TVG ultrasound
HUMAN CHORIONIC GONADOTROPIN (hCG)
• determination:
– biologic assays
– immunologic:
• radioimmunoassay (RIA, sensitivity 5mIU/ml)
• immunoradiometric assay (IRMA, sensitivity 150mIU/ml)
• ELISA (sensitivity 25-150mIU/ml)
• fluoroimmunoassay (sensitivity 1mIU/ml)
• latex agglutination inhibition tests (urine)
• radioreceptor assay
• high sensitivity pregnancy tests (<1mIU/ml) - sometimes
false positive because of endogenous pituitary hCG
FUNCTION OF hCG
• maintains corpus luteum
• stimulates:
– progesterone production by the corpus luteum
– Leydig cells of male fetus to produce
testosterone (?)
– fetal adrenal steroidogenesis
• immunosupressive (lymphocyte modulator)
• thyrotropic activity
• induction of ovulation
HUMAN PLACENTAL LACTOGEN (hPL)
HUMAN SOMMATOMAMMOTROPHIN (hCS)
• single chain polypeptide
• produced 3 wk. post conception; detected in
serum 5-6 wk. post conception
• highest levels III trimester, disappears after
delivery
• production proportional to placental mass
• determination: RIA
Role of hPL during pregnancy
HUMAN PLACENTAL LACTOGEN (hPL)
HUMAN SOMMATOMAMMOTROPHIN (hCS)
Growth hormone (GH and PRL-like effects) :
– induces lypolysis,  plasma FFA
– inhibits glucose uptake and
gluconeogenesis, glucose intolerance
– insulinogenic effect ( insulin)
– hyperinsulinemia
–  plasma IGF-I
CORTICOTROPIN RELEASING HORMONE (CRH)
• produced in cytotrophoblast (max. at term)
• stimulates placental ACTH release
•  circulating maternal levels
ADRENOCORTICOTROPIN (ACTH)
• structurally similar to pituitary ACTH
•  circulating maternal levels
• hypercortisolism
DECIDUAL PROLACTIN (PRL)
• similar to pituitary prolactin
• regulates fluid and electrolyte flux through
fetal membranes
• secreted independently of fetal/maternal
dopaminergic control
• ALSO maternal and fetal pituitary PRL
• maternal serum PRL  (100-200ng/ml)
• AF PRL  until 20wk. (1000ng/ml) then 
PLACENTAL PROTEIN 14 (PP14)
• immunosupresive peptide
• secreted in decidualized endometrium
• circulating marker of decidual growth
ALPHA-FETALPROTEIN (AFP)
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•
•
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synthesized in YS, GI and fetal liver
osmoregulator of fetal intravascular volume
 AFAFP and MSAFP in neural tube defects
 MSAFP in pregnancies with Down syndrome
PREGNANCY STEROIDS
• Estrogens:
– estradiol
– estriol
– estrone
• Progestogens:
– progesterone
– 17alpha-OHprogesterone
• Adrenocorticoids:
– cortisol
ESTRIOL
• 1000 x more than in non pregnant state
• 90% of all estrogens in pregnancy
• exclusively produced by placenta (conversion of
16alpha-DHEA-S) - only living fetus
• detectable at 9th wk. (0,05ng/ml) ; at term (30ng/ml)
ESTRADIOL / ESTRONE
• produced by maternal sources (estradiol-ovaries: 5-6
wk.; estrone-ovaries, adrenal: 4-6wk.), gradually
placenta, after I trimester major source (conversion of
circulating DHEA-S)
• after conception range 5-30ng/ml
MATERNAL PLASMA UNCONJUGATED
ESTROGENS
Estradiol
Estriol
Estrone
ESTRIOL
• extremly low levels or no estriol:
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–
–
–
fetal demise, anencephaly
CAH
placental sulfatase deficiency
hydatidiform moles
• decline in estriol production or failure to rise:
– maternal renal disease, PIH, preeclampsia or eclampsia
– IUGR
• large quantities:
– multiple pregnancy
– Rh isoimmunisation
ESTROGENS - HORMONAL FUNCTION
• augment uterine blood flow
• placental steroidogenesis: regulation of
progesterone synthesis
• parturition:
– ripen the cervix
– initiate uterine activity
– augment established labor
–  sensitivity of myometrium to oxytocin
PROGESTERONE
• production during pregnancy:
– corpus luteum (only source till 6th wk.)
– placenta (6th wk. -> 12th wk. -> parturition )
luteoplacental shift: 7-8th wk of pregnancy
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•
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production independent of fetus
conception cycle: sustained slow rise
early pregnancy: 10-35ng/ml, 100mg/day
at term: max. 100-300ng/ml, 250mg/day
MATERNAL PLASMA PROGESTERONE
PROGESTERONE HORMONAL FUNCTION
• modulates tubal motility (preimplantation
conceptus)
• inhibits maternal-fetal tissue rejection
• antagonizes estrogen-augmented uterine
blood flow
• induces uterine relaxation (stabilization of
lysosomal membranes and inhibition of PG
production)
Steroidogenesis in fetus & placenta
OVARIAN
STEROIDOGENESIS