Role of Hormones (to Do) Flashcards

1
Q

what hormones maintain uterine quiescence

A

progesterone
relaxin
nitric oxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

do systemic plasma levels represent local hormone changes?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

describe changes that cause activation of mymometrial cells

A

increased oestrogen : progesterone ratio
(oestrogen facilitates contractions, progesterone inhibits)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what hormones ripen cervix

A

prostaglandins
relaxin
nitric oxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

when does myometrium respond to prostaglandins and oxytocin

A

when myometrial cells are activated (O>P)
Cervix is ripe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

HcG

where is it secreted from
when can it be detected
function

what does high HcG indicate / cause

A

human chorionic gonadotrophin

secreted from - trophoblast
detected blood (day 9), urine (10-12) post fertilisation

Role
- prevents degeneration of Corpus luteum + stimulates CL to secrete oestrogen + progesterone
- influence change in smell / taste / saliva
- may have immunosuppresant role (so maternal body doesn’t reject placenta)

high hcg may indicate molar pregnancy / hyperemesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Oestrogen - in reproduction cycle
type of oestrogen
what secretes this hormone
who synthesizes oestrogen
what are functions (in reproductive cycle + pregnancy)

A

Secreted
-by follicle cells in ovaries
- Corpus luteum (until wk 7)
- placenta

type- ostradiol

stimulated by
FSH (mainly) + LH

Function

reproductive cycle
- develo and maintain female reporductive structures
- maintaining fluid / electrolyte balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Oestrogen- in pregnancy
what secretes this hormone
who synthesizes oestrogen
what are functions

A

Secreted
- Corpus luteum (until wk 7)
- placenta

type- oestriol (oestradiol is main source in non-pregnancy)

synthesis
- synthesized from woman, fetus, placenta

Function
overall- role is to stimulate tissue growth
* -uterus- hyperplasia +hypertrophy + vascularisation
* breast development
* swelling + softening of connective tissue (symphysis pubis dysfunction, ligament pain)
* fluid retention

also
increase uterus’s sensitivity to progesterone
increase sensitivity to CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Progesterone - in pregnancy
where is it secreted
how is it synthesized
Functions and amount in pregnancy
change in labour

A

secreted from- Corpus luteum (<7wks), placenta

Synthesis is NOT reliant on fetal dev

functions
1) stimulates Decidua secretions (support early implantation)

2) RELAXES smooth muscle
* `uterine contractions
* ureters (stasis), * stomach (nausea + vomiting) + intestines (constipation), osophogeal sphincter (heartburn), reduced peripheral resistance (haemorrhoids + varicose veins, postural hypotension)

3) stimulates ventilation at lower PaCO2 (increases sensitivity of maternal chemoreceptors) (thus can stimulate hyperventilation)

4) suppreses immunological response

5) precursor to fetal adrenal hormone
6) increases body temp

Amount
increases throughout pregnancy. Drop rapidly after placenta removed

labour
- in labour, oestrogen > progesterone (enabling cx of uterine muscle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Progesterone (non-pregnancy)
where is it secreted
how is it synthesized
Functions and amount in pregnancy
change in labour

A

secreted from- Corpus luteum

stimulated by LH

functions
- prepare endometrum to receive fertilised ovum
- prevent sperm motility (thicken mucous)
- increse body temp
- relax fallopian tube muscles to support ovum passage to uterus

Amount
peak post ovulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

GnRH

where is is produced?
function
what hormones inhibit GnRh

A

produced by hypothalamus

function
- Stimulates Anterior pituitary gland to release FSH + LH

Inhibited by
oestrogen + progesterone
prolactin can inhibit GnRH (lactational amenorrhea)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

prolactin
function
where is it secreted
what inhibits it

A

function-
- Antenatally- development of mammary glands
- lactation (lactogenesis II)

secreted from - APG (stimulated by nipple stimulation)

inhibited by
- Antenatally- Progesterone, human placental lactogen, prolactin inhibiting factor (from hypothalamus) inhibit prolactin from binding to receptors (inhibits lactogenesis)

Positive Feedback

levels
- increase in pregnancy- surge at birth and reduce after 6 weeks in BF women

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Lutenising hormone
where is it secreted from
function
inhibited by

A

LH
secreted from APG
stimulated by GnRH

Function
act on thecal cells- iinhibit FSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

FSH

A

Follicle stimulating hormone

function
- develop follicles in ovary as part of ovarian cycle
-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what triggers ovulation

A

LH surge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

corticotrophin releasing hormone

where is it produced
levels in pregnancy
function

A

Hormone that has an important role in onset of labour

produced by
hypothalamus, placenta, decidua, membranes

levels in pregnancy
- increase significantly >35wks, drop after birth
- higher with PTL, PIH, IUGR

function- dual role!
- in pregnancy- uterine quiescence
- labour- when combined with oxytocin- it promotes Cx

17
Q

Prostaglandins
how do they work
where are they synthesized
functions
influenced by

A

LOCAL hormones/ paracrine hormones- they act locally where they are synthesized

synthesized - decidua / - placenta/ - cervix / fetal membranes

function
-uterotonins (directly responsible for labour)-
* - stimulate muscle fibres to contract
* formation of gap junctions
* increase Ca levels
soften the cervix (enable effacement / dialtion)

influenced by
- oxytocin>progesterone
- oxytocin promotes prostaglandin release

18
Q

oxytocin

A

where is it released
- Left pituitary gland (into systemic circulation)
- membranes, decidua, placenta

mechanism
- stretch receptors detect pressure–> stimulate hypothalamus to produce oxytocin, Left pituitary gland releeses –> oxytocin stimulates contractions

  • function
    SUPPORT uterine contractions (NOT primary uterotonin!!)
  • milk let down
    -emotional attachment
19
Q

Oestrogen in labour
what is role
what is oestrogen infleunced by?

A

FACILITATES myometrial contractility (but doesn’t directly cause contractions)
(INFLUENCED BY MATURE FETUS)

Function
- increases sensitivity of oxytocin receptors
- promotes formation of CAPs
promotes prostaglandin synthesis

Oestrogen >progesterone to enable labour

20
Q

Which prostaglandins are most important

A

E AND f

21
Q

progesterone in labour

A

Role - SUPPRESSES uterine excitement
- Calcium uptake
- inhibit CAPs
-decrease oxytocin

NOT influenced by fetus

22
Q

Relaxin -
function, where is it produced, and level in pregnancy

A

level - highest in T1, fall rapidly after birth

produced
- myometrium, decidua, placenta

function
- Uterine quescence
- inhibit oxytocin
- cervical ripening (which seems contradictory!)

23
Q

nitric oxide

A

function
-myometrial quiescence
interacts with progesterone to inhibit CAPs