Part 17: Gonadal Hormones Flashcards
1
Q
the gonadal hormones are also known as ____
A
sex hormones
2
Q
t/f sex hormones are involved in more than just reproduction
A
t
3
Q
LH and FSH are secreted by the ____ gland to act on the ___ and ___
A
pituitary; testes & ovaries
4
Q
stimulation of ovaries & testes by LH and FSH causes them to release ___
A
estrogens and androgens
5
Q
sex hormones exist in a ___ feedback system
A
negative
6
Q
androgens and estrogens cause negative feedback by looping back to the ___ and ___ glands
A
pituitary and hypothalamus
7
Q
the frequency of ____ from the hypothalamus detrmines which pituitray hormone is released
A
pulsatile release of gonadotropin releasing hormone
8
Q
what releases GnRH?
A
hypothalamus
9
Q
what releases LH and FSH?
A
pituitary gland
10
Q
what is the role of LH?
A
androgen release, ovulation
11
Q
what is the role of FSH?
A
follicle development & spermatogenesis
12
Q
which hormone will be released by pituitary if there is a high frequency of GnRH release from the hypothalamus?
A
LH
13
Q
which hormone will be released by pituitary if there is a low frequency of GnRH release from the hypothalamus?
A
FSH
14
Q
which hormones are released from the pituitary if there is constant release of GnRH from the hypothalamus?
A
neither FSH or LH
15
Q
give 2 examples of what synthetic GnRH can be used to treat
A
infertility; some types of hormone sensitive cancer
16
Q
what is the main role of FSH in males?
A
starting puberty and sperm maturation
17
Q
____ is the primary hormone that stimulate the making of testosterone
A
LH
18
Q
where is testosterone made?
A
Leydig cells of the testes
19
Q
testosterone is made from ___
A
cholesterol
20
Q
testosterone circulates in the blood by being bound to ___ protein
A
sex hormone binding globulin (SHBG)
21
Q
testosterone binds to ___ receptors
A
intracellular androgen receptors
22
Q
once inside target cells, testosterone is converted to ___ by ___ enzymes
A
dihydrotesterone (DHT); 5-alpha reductases
23
Q
which is a higher potency agonist at androgen receptors, testosterone, or DHT?
A
DHT
24
Q
the activated androgen-receptor complex is translocated to the ____ where it modifies gene ___ and ___ synthesis
A
nucleus, transcription; protein synthesis
25
t/f many of the androgenic effects we often associate with testosterone are actually caused by DHT
t
26
which androgen is responsible for the development of male secondary sex characteristics?
DHT
27
testosterone is important in early development and throughout life it is involved in the production and maintenance of ___, ___ , __and ___
muscle mass; red blood cells; bones; hair growth
28
testosterone can also be metabolized by CYP19 (aromatase) into ___
estradiol
29
the estrogens made from testosterone is important for ___ in males
bond density
30
the levels of estrogen in males is typically ____ (high or low)
low
31
t/f aromatase enzymes are expressed in fat cells, so obese men can express more estrogen and a decrease in testosterone
t
32
what are the 2 categories testosterone modulation falls into?
replacement or suppression therapy
33
androgen ____ therapy is used for low T syndrome
replacement
34
androgen ____ therapy is used for performance enhancement
replacement
35
androgen ____ therapy is used for treatment of prostate enlargement
suppression
36
androgen ____ therapy is used for treatment of hormone sensitive prostate cancer
suppression
37
what is low T syndrome?
circulating levels of testosterone are insufficient to maintain normal physiologic roles of androgens
38
t/f testosterone levels dcline with age
t
39
what are some of the symptoms of low T?
low sex drive, fatigue, hair loss, reduced muscle mass
40
t/f replacing testosterone can effectively manage low T symptoms
t
41
t/f the lipophilicity of steroid hormones make it possible to administer them transdermally
t
42
what are the benefits of transdermal testosterone?
slow release, easy, avoids 1st pass metabolism
43
what is a major downfall of oral testosterone treatment?
most will be metabolized before reaching systemic circulation
44
how is testosterone for performance typically administered?
high dose my IM injection
45
why is testosterone for performance typically given IM?
to target the muscle they want to grow and avoids 1st pass metabolism
46
what is Androderm?
testosterone transdermal patch
47
t/f androgens are involved in prostate enlargement
t
48
what is benign prostatic hyperplasia (BPH)?
a benign prostate enlargement
49
what is a common symptoms of enlarged prostate?
urinary retention
50
why does enlarged prostate cause urinary retention?
obstruction of the urethra
51
does prostate cancer have a high level of metastasis?
yes
52
ketoconazole and spironolactone are anti-androgens that work by what way?
inhibit testosterone biosynthesis
53
what is a concern when usifg ketoconazole to inhibit testosterone synthesis?
a CYP3A4 inhibitor which can lead to a lot of interactions
54
why are ketoconazole and spironolactone not commonly used as androgen suppressors?
they both have other systemic effects and there are drugs that are more specific to target androgen production
55
how is finasteride used as an anti-androgen?
inhibits the conversion of testosterone to DHT by inhibiting the 5-alpha reductase enzymes
56
how does flutamide work as an anti-androgen
androgen receptor antagonist
57
an important consideration when using finasteride or flutamide as anti-androgens is that blocking these pathways allows for more ____
free testosterone that can be converted into estradiol
58
what is a side-effect of finasteride and flutamide as a result of increased estradiol?
increased breast tissue
59
what are the 5 hormones involved in female reproduction?
progestins, estrogens, human chorionic gonadotropin (hCG), oxytocin, prolactin
60
which female hormones are directly involved in the menstrual cycle and female reproductive development?
progestins and estrogens
61
____ is a hormone produced during early embryo development, is excreted in urine and is used in at-home pregnancy tests
human chorionic gonadotropin (hCG)
62
what hormone is involved in uterine contractions during birth?
oxytocin
63
what hormone is involved in milk production and lactation?
prolactin
64
what are the 4 stages of the menstrual cycle in order?
follicle development, ovulation, endometrium proliferation, and menstruation
65
what is the important hormone during the follicular phase?
FSH
66
follicle secrete what hormone as they develop?
estrogen
67
increased estrogen levels results in a ____ feedback on FSH levels and ____ feedback of LH levels
negative; positiev
68
LH spike triggers ____
ovulation
69
after ovulation, ___ and ____ levels rise
progesterone and estrogen
70
estrogen and progesterone is secreted by the ____
corpus luteum
71
what is the effect of estrogen and progesterone release after ovulation?
endometrial changes that favour implantation of a fertilized egg
72
a drop in ___ and ___ hormones initiates menstruation
estrogen and progesterone
73
t/f estrogen and progesterone have negative feedback effects throughout most of the menstrual cycle
t
74
during follicle development, there is a ___ feedback loop between estradiol and LH, resulting in the LH surge needed for ovulation
positive
75
estrogen and progesterone have nagative feedback loops on ___ and ___
FSH and GnRH
76
estrogens and progesterone are produced mainly in the ____
ovaries
77
is testosterone produced in the ovaries?
yes actually
78
___ is the starting material for estrogen, testosterone, and progesterone
cholesterol
79
____ enzymes are used in the process of making estrogen
aromatases
80
t/f there are many similarities between the male and female hormone systems, but it is teh balance of the hormones made that makes the difference
t
81
bc androgens and estrogens are made by the same pathway, altering production of one will have an impact om the other
t
82
what is the most common pharm modulation of estrogens and progestins?
hormonal contraceptives to prevent pregnancy
83
estrogens and progesterones used as hormone replacement are typically dosed ___ (higher or lower) than contraceptives
lower
84
give 2 examples of local progestin administration for birth control
IUD and nuva ring
85
how does hormonal contraception work?
reinforces the negative feedback loop to prevent LH surge, which inhibits ovulation, no egg, no pregnancy
86
progestin-containing contraceptives have negative feedback on ___ and ___ hormones
LH and FSH
87
what is the main goal of hormonal contraception?
increase the negative feedback loop so the positive feedback loop does not occur and ovulation is prevented
88
estrogen ___ the endometrium
increses
89
progesterone ___ the endometrium
decreases (lighter periods)
90
if estrogen was given alone, it could cause ___
endometrial cancer
91
t/f estrogen is always given at the lowest effective dose and always with progesterone
t
92
the continual presence of progesterone makes the uterus unfavourable for _____
implantation of a fertilized egg
93
progesterone ____ the movement of sperm
slows
94
progesterone ____ cervical mucus production
increases
95
what is ethinyl estradiol?
an estrogen used for contraception
96
t/f progestin only products need to be taken at the same time every day to maintain adequate hormone levels
t
97
depot injections typically last ___ weeks
12
98
IUDs like mirena last up to ___ years
5
99
what is the most common side effect with prolonged progestins?
breakthrough bleeding or spotting related to the shedding of the endometrial lining
100
t/f the breakthrough bleeding of progestins typically resolves over time
t
101
t/f many patients using IUD or depot tend to cease menstruation all together
t
102
give an example of a progestin only contraceptive
micronor: norethindrone
103
androgenic progestins may increase ___ and ___ as side effects and non-androgenic progestins have the oppposite effects
weight gain & acne
104
what is the active ingredient in the depo-provera shot?
medroxyprogesterone acetate
105
what is the active ingredient is the Mirena IUD?
levonorgestrel
106
when a contraceptive with a progestin that is highly structurally similar to progesterone, it can be metabolized into _____ in the body
testosterone
107
when the progestin in BC is converted into testosterone, it can cause what side effects?
weight gain, acne, hair growth
108
are non-androgenic progestins structuarlly related to progesterone? Can they be converted into testosterone?
no ; no
109
give an example of an androgenic progestin?
norethindrone
110
give an example of a non-androgenic progestins
dropirenone
111
t/f the combination estrogen and progestin hormonal contraceptives are the most common birth control pills
t
112
t/f ethinyl estradiol is commonly used, but many different progestins are used
t
113
t/f there are many different varieties of dosing regimens
t
114
t/f combination birth controls cause an "artificial menstrual cycle"
t
115
what are the active ingredients in Yaz?
ethinyl estradiol & drospirenone
116
how does combination BC like Yaz work?
phasic cycles of hormone levels mimic physiologic levels to maintain the menstrual cycle but prevent the LH spike that would cause ovulation
117
what are some common side effects of elevated estrogen from BC? Are they reversible?
nausea, edema, migraines; usually resolve after prolonged use or when the dose is lowered
118
what are some of the serious side effects of estrogen in BC? What increases these risks?
CV (MI, blood clots, stroke); smoking and being older than 35 years
119
what can be done if a patient on a combo BC continues to have migraines and increased CV risk?
can be switched to progestin only pill
120
what is the failure rate of OCs?
7%
121
what is the failure rate of barrier methods like condoms?
13%
122
what can cause low hormone levels leading to contraceptive failures?
missing pills or improper administration, drug interactions, or other physiologic changes
123
t/f blood monitoring for hormone levels following BC use is possible, but not done unless there is a compelling reason
t
124
estrogens and progestin are metabolized by ____ enzymes, meaning many drug interactions are possible
CYP3A4
125
are CYP3A4 inducers or inhibitors more likely to decrease BC hormones?
CYP3A4 hormones
126
if using a combo BC rather than just progesterone, you are ___ (more or less ) likely to avoid failure due to drug interactions
less
127
the effect of enterohepatic circulation would be ____ (more or less) prominent when using an alternative dosage form like the IUD or depo shot
less
128
t/f the Mirena also prevents egg implantation by providing a physical barrier
t
129
the overall effectiveness of IUDs like Mirena is reported to be greater than ___
99%
130
is antibiotic use while on BC directly linked to failure leading to pregnancy?
no
131
what is the fail rate of depot progestin injections?
4%
132
what is the failure rate of surgical sterilization?
0.1-0.5%
133
what is the effect of phenytoin on BC?
CYP3A4 inducer (reduce circulating hormones)
134
what is the effect of antibiotics on BC?
reduce GI enterohepatic circulation hormones and increase CYP3A4
135
which antibiotic has been linked to possible contraceptive failure?
rifampin
