menopause Flashcards
(30 cards)
whats the main player in hormonal regulation
hypothalamus
what 2 nuclei in the hypothalamus react to the levels of oestrogen to control temp and reporduction
AVPV nuclei
Arc nuclei
how does the hypothalamus affect the release of hormones related to reproduction, what 2 hormones are they
hypthalamus controls pituitary hormone release
- GnRH (gonadotropin releasing hormone)
- PIH /dopamine (prolactin inhibiting hormone)
what is 3 roles of the anterior pituitary gland (across male and females)
- stimulates production of oestrogen and progesterone
- ovulation and pregnancy
- testosterone production and spermatogenesis (males)
what 3 hormones are released by APG
- FSH follicle stimulating hormone
- Lutenizing hormone LH
- prolactin PRL
How do high/low levels of oestrogen affect hypothalamus
high = positive feedback, hypothalamus more sensitive to GnRH (from PG) = surge in LH (triggering ovulation)
low = negative feedback, low oestrogen inhibits LH/FDH due to increased progesterone (from follicle)
how does high/low oestrogen specifically target Arc or AVPV nuclei and thus control temperature
High oestrogen = excites neurone in AVPV = surge in LH release
- as AVPV influences thermoregulation, enhanced activity in AVPV = DECREASE in body temp
Low oestrogen = arc nuclei responds to negative feedback of GnRH, low oestrogen = instability in KNDy neurones in Arc nucleic = erratic firing patterns affecting thermoregulatory dysfunction = increased SYMPATHETIC outflow = hot flushes
(low oestrogen = unstable arc nuclei = triggering of sympathetic system = hot flush)
what is the hypothalamus/ body reaction to high and low temps
high temp = cooling response
- blood vessels dialate
- skin perspires (sweating)
- breathing rate increases
low temp= warming repsonse
- blood vessels constrict
- muscles shiver
- thyroid hormones increase metabolic rate
why does low levels of oestrogen = low metabolic activity and obesity
as it acts on the hypothalamus to regulate all aspects of body energy and metrabolism
know: oestrogen affect reproduction AND. metabolism
oestrogen has a non-genomic effect, what does this mean
any action that does not affect gene expression initially or directly, but that does induce rapid effects, such as activation of signal transduction pathways.
role of oestrogen
look at screenshot
what is POI
primary ovarian insufficiency
- loss of ovarian function in young women (not related to menopause)
what are some causes of POI
cancer treatment
genetics
infections e/g tuberculosis
what is peri-menopause, when does it begin roughly
time before FULL cessation of menstural cycle
- levels of oestrogen start decreasing
- around 40
what is menopause, age range?
no menstruation for 12 months
- around 50
what procedure can trigger menopasue
hysterectomy with bilateral oophorectomy (removing both ovaries)
what are menopause symptoms due to
loss of oestrogen
how does monopause affect lh/fsh and gnrh
no follicles (menopause) = no oestrogen
- hypothalamus tries releasing MORE GNRH to stimulate ovaries
- in return the GnRH keeps causing pituitary gland to release LH/FSH but not follicle is coming so it just builds up
overall = there is large increase of LH/FSH and GnRH
despite menopause having no follicles thus no oestrogen release, where else can low levels of oestrogen be released from
adrenal glands (from testosterone)
what is VMS
vasomotor symptoms (hot flushes and night sweats)
why do ppl on menopause get cold and hot very quick
people have an average temperature range,
ppl on menopause have a smaller temperature range so what we might find normal, they might find hot or cold
vasomotor symptom can be mild, moderate and severe, define them
mild = feel hot, no sweat
moderate = feel hot and sweat
severe = feel hot, sweat and have to cease activity
oestrogen inhibits neurons (for thermoregulation) in hypothalamus before menopause and another activates it in delicate balance BUT
hyper activation of those neurones = cutaneous vasodilation = hot flush
