estrogen Flashcards
(110 cards)
1
Q
where are GnRH neurons
A
in the hypothalamus
2
Q
what is GnRH
A
gonadotrophin releasing hormone
3
Q
when do GnRH neurons fire
A
at hourly intervals
4
Q
where does the GnRH act
A
on anterior pituitary gland (gonadotropes)
5
Q
where are gonadotropes
A
anterior pituitary gland
6
Q
what do the gonadotropes release
A
gonadotrophins
7
Q
what are the 2 gonadotrophins
A
luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
8
Q
where does LH and FSH act
A
on the ovary
9
Q
what does the ovary release
A
estrogen and progesterone
10
Q
when in the menstrual cycle does LH peak
A
right before ovulation
11
Q
when in the menstrual cycle does FSH peak
A
right before ovulation
12
Q
when in the menstrual cycle does estradiol peak
A
before ovulation, then a bit more later in the cycle
13
Q
when in the menstrual cycle does progesterone peak
A
later in the cycle, day 21
14
Q
what causes LH and FSH peak in the menstrual cycle
A
estrogen acting as a positive regulator on the gonadotrophins until the ovum is released
15
Q
what does estrogen do to the gonadotropes usually
A
inhibit
16
Q
what does progesterone do to the gonadotropes
A
inhibit
17
Q
what does progesterone do to the hypothalamic GnRH neurons
A
inhibit
18
Q
where does estrogen inhibit
A
anterior pituitary gonadotrope glands
19
Q
where does progesterone inhibit
A
anterior pituitary gonadotrope glands and hypothalamic GnRH neurons
20
Q
what is E2
A
estradiol
21
Q
what is another name for estradiol (2)
A
E2 or estradiol-17β
22
Q
what are the 3 types of estrogens
A
E1 - estrone
E2 - estradiol
E3 - estriol
23
Q
which estrogen is the most potent
A
E2
24
Q
which estrogen is the main endogenous estrogen
A
E2
25
where is E2 synthesized in females
in the ovary and placenta
26
where is E2 synthesized in males
testis and adrenal cortex
27
what is the name for E1
estrone
28
what is the name for E2
estradiol
29
what is the name for E3
estriol
30
how potent is E1
not, low binding affinity for estrogen receptors
31
how potent is E3
not, low binding affinity for estrogen receptors
32
where is E1 synthesized
in liver from estradiol
| in peripheral tissues from androstenedione and other androgens
33
where is E3 synthesized
in liver from estradiol
| in peripheral tissues from androstenedione and other androgens
34
which E is made in the ovaries
E2
35
which E is made in the liver
E1 and E3
36
where is estradiol metabolized
into the liver
37
what is estradiol metabolized into
estrone, estriol, conjugated metabolites
38
what is estradiols binding to albumin like
weak
39
how long is the half life for estradiol
short, only minutes
40
what is SHBG
sex hormone binding globulin
41
what is estradiols binding to SHBG like
stronger
42
where does estradiols bind weak
albumin
43
where does estradiols bind strong
SHBG (sex hormone binding globulin)
44
what increases sex hormone binding globulin
estrogen and thyroid hormone
45
what decreases sex hormone binding globulin
androgen and growth hormone
46
where are estradiol conjugated metabolites excreted
in bile then GI tract
47
what happens with estradiol conjugated metabolites in the GI tract
they may be hydrolyzed to active estrogen in GI tract and reabsorbed (via bacteria)
48
what can antibiotics do to birth control efficacy and why
decrease cause less estrogen can be made in GI from the estradiol conjugated metabolites
49
how do non genomic actions of estrogen work
rapid effects via plasma membrane estrogen receptors
50
what does estrogen do to acute blood vessel diameter
acute vasodilation
51
how do genomic actions of estrogen work
intracellular estrogen receptors, ERα and ERβ
52
where are ERα and ERβ
in female reproductive tract, breast, pit, hypo, bone, liver, etc
53
what does ERα and ERβ receptor activation cause
changes in gene transcription
54
how are synthetic estrogens made (what are 2 types)
- chemical alternations to the estrogen molecule
| - non-steroidal compounds with estrogenic activity
55
why do we make synthetic estrogens from chemical alternations to the estrogen molecule
to increase the effectiveness of oral administration
56
what are non-steroidal compounds with estrogenic activity structurally like
presence of phenolic A ring which is important for binding to ER
57
what does estrogen do to growth spurt
helps with the long bones and epiphyseal closure
58
what does estrogen do to female maturation
- growth of vagina uterus fallopian tubes
| - secondary sex characteristics
59
what are 3 female secondary sex characteristics
- enlargement of breasts
- changes in distribution of body fat
- growth of axillary and pubic hair
60
what does estrogen do to endometrium
increase in thickness and vascularity of endometrium
61
what does estrogen do to regulation of menstrual cycle
brief positive feedback on the pituitary to stimulate pre-ovulatory LH and FSH surge mid cycle
62
what does estrogen do to progesterone receptors + where
increases progesterone receptor synthesis in uterus vagina pituitary and hypothalamus
63
what does estrogen do to blood + how
increase coagulation - decrease in anticoagulation factors
64
what does estrogen do to bone
decrease in resorption by increase osteoclast apoptosis and decreasing the maturation of osteoclasts
65
what does estrogen do to osteoclast
increase apoptosis and decrease maturation
66
what does estrogen do to binding proteins
increase levels of corticosteroid-binding globulin, sex steroid-binding globulin and thyroxine-binding globulin
67
what does estrogen do to plasma lipids (3)
```
increase HDL (good) decrease LDL (bad)
small increase in triglycerides
```
68
what does estrogen do to HDL
increase
69
what does estrogen do to LDL
decrease
70
what does estrogen do to triglycerides
small increase
71
what does estrogen do to salt and water intension and how
increase likely by ADH release
72
what are 4 therapeutic uses of estrogen
- primary hypogonadism
- amenorrhea
- birth control
- postmenopausal hormonal therapy
73
what is estrogen often combined with therapeutically
progesterone
74
what is primary hypogonadism
failure of ovarian development
75
what are 3 uses of postmenopausal hormonal therapy
decrease vasomotor symptoms
reduce genitourinary syndrome
reduce osteoporosis
76
what are 4 vasomotor symptoms of menopause
- hot flashes
- inappropriate sweating
- irritability, difficulty concentration, mood changes
- insomnia
77
what are 3 genitourinary symptoms of menopause
- genital dry/burn/irritation
- sexual pain / less lubrication
- urinary urgency, dysuria, UTIs
78
what is dysuria
painful or difficult urination
79
what are 2 main untoward effects of estrogen
cancer (breast and endometrial)
| embolisms
80
what kinds of cancer are common with estrogen
breast and endometrial
81
how can you reduce the risk of endometrial carcinoma with estrogen
progesterone supplement (prevents proliferation caused by E)
82
what does estrogen do to embolisms
small increase risk of pulmonary embolism and venous thromboembolism
83
what are 4 contraindications for estrogen
- estrogen dependent cancer
- undiagnosed genital bleeding
- history of thromboembolic disorders
- liver disease
84
what was the point of the womens health initiative
assess the major health benefits and risks associated with the use of estrogen or combined estrogen/progestin preparation in hormone replacement therapy
85
what is the most effective treatment for vasomotor symptoms and genito-urinary syndrome
hormone therapy
86
what can hormone therapy do to bone loss and fracture
prevent
87
who is hormone therapy most beneficial for
women under 60 or within 10 years of menopause with VMS and high risk for bone loss/fracture
88
who is hormone therapy least beneficial for
women over 60 or more than 10 years of menopause due to coronary heart disease, stroke, thromboembolism, and dementia risk
89
what was the conclusion of womens health initiative
therapy with estrogen/progestin or 5.6 years or estrogen for 7.2 years was not associated with all-cause, cardiovascular or cancer mortality during cumulative follow-up of 18 years
90
what do anti-estrogen drugs do / mechanism of action (tamoxifen)
partial agonist inhibitor of estrogen receptor
91
what is tamoxifen
anti-estrogen
92
what is mechanism of action of tamoxifen
partial agonist inhibitor of estrogen receptor
93
what does tamoxifen have estrogenic effects on (4)
- bone (less osteoporosis)
- plasma lipids (more HDL good)
- endometrium (cancer!)
- blood coagulation (clot!)
94
what does tamoxifen have anti-estrogenic effects on (1)
breast tissue
95
what are non estrogen receptor mediated actions if tamoxifen
modulation of signalling proteins and activation of apoptosis
96
what can be a good use of tamoxifen and why
breast cancer because it has anti-estrogenic effects on breast tissue
97
what are 2 types of aromatase inhibitors
steroidal or non steroidal inhibitor of aromatase
98
what do aromatase inhibitors do
selective inhibition of estrogen synthesis
99
what are aromatase inhibitors used for
breast cancer
100
what does aromatase inhibitors do to estrogen synthesis
reduce
101
do aromatase inhibitors stimulate endometrial tissue
no
102
do aromatase inhibitors increase risk of uterine cancer
no
103
do aromatase inhibitors increase risk of venous thromboembolism
no
104
do aromatase inhibitors have a beneficial effect on bone
no
105
what is the mechanism of action of clomiphene
anti-estrogen : reduces estrogen binding in gonadotropes, decrease in negative feedback
106
what does anti-estrogen clomiphene do to gonadotrophins
increase secretion of them (LH FSH)
107
what does anti-estrogen clomiphene do to estrogen secretion
increase
108
what does anti-estrogen clomiphene do to ovulation
increase
109
what is the use of anti-estrogen clomiphene
treatment of infertility and amenorrhea
110
what are 5 unwanted effects of anti-estrogen clomiphene
- ovarian enlargement
- ovarian cysts
- hot flashes
- blurred vision
- multiple births
