Endocrinology Part 4 - Gonadal Hormones Flashcards
1
Q
ovarian hormone synthesis
A
Ovarian Steroidogenesis
2
Q
testicular hormone synthesis
A
Testicular Steroidogenesis
3
Q
enzyme that converts cholesterol to pregnenolone
A
cholesterol side-chain cleavage enzyme
4
Q
enzyme that converts pregnenolone to progesterone
A
3-beta-hydroxysteroid dehydrogenase
5
Q
enzyme that converts progesterone to 17-OH progesterone
A
17-a-hydroxylase
6
Q
enzyme that converts pregnenolone to 17-OH-pregnenolone
A
17-a-hydroxylase
7
Q
enzyme that converts 17-OH-pregnenolone to 17-OH-progesterone
A
3-beta-hydroxysteroid dehydrogenase
8
Q
enzyme that converts DHEA to androstenedione
A
3-beta-hydroxysteroid dehydrogenase
9
Q
enzyme that converts 17-OH-pregnenolone to DHEA
A
17,20-Lyase
10
Q
enzyme that converts 17-OH-progesterone to androstenedione
A
17,20-Lyase
11
Q
enzyme that converts DHEA-S to DHEA
A
sulfotransferase
12
Q
enzyme that converts androstenedione to testosterone
A
17-beta-hydroxysteroid dehydrogenase
13
Q
enzyme that converts testosterone to dihydrotestosterone
A
5-a-reductase
14
Q
where does conversion of testosterone → estradiol and androstenedione → estrone takes place?
A
Ovaries
Peripheral tissues (aside from testes & ovaries)
15
Q
females have testosterone due to this presence
A
DHEA
16
Q
events that occur in peripheral tissues during ovarian/testicular steroidogenesis
A
- testosterone → (reduced) → dihydrotestosterone
- adrenal androgen (DHEA) → testosterone
- estriol (type of estrogen) → (hydroxylated) →estradiol
- testosterone → estradiol
- androstenedione → estrone
17
Q
More potent than testosterone
A
Dihydrotestosterone
18
Q
Responsible for masculinization of external genitalia (male gonads)
A
Dihydrotestosterone
19
Q
What occurs when ↑ dihydrotestosterone in female
A
masculinization of female external genitalia
20
Q
percentage of protein bound sex hormones
A
98-99%
cannot fuse to the vascular system → cannot interact with the target cells
21
Q
percentage of free/unbound sex hormones
A
1-2%
biologically active
22
Q
TRANSPORT PROTEINS OF GONADAL HORMONES
A
Sex Hormone-Binding Globulin (SHBG)
Corticosteroid-Binding Globulin (CBG)
Albumin
23
Q
Transports androgens and estrogens
A
Sex Hormone-Binding Globulin (SHBG)
24
Q
Binds adrenal cortex hormones
A
Corticosteroid-Binding Globulin
25
Delivers progesterone & glucocorticoids (cortisol)
Corticosteroid-Binding Globulin
26
Principal androgen hormone in the blood
TESTOSTERONE
27
Most potent androgen among male
TESTOSTERONE
28
T/F
testosterone is only found in men
F
Testosterone → estrogen among female
29
95% of testosterone are synthesized by
Leydig cells of testis
30
5% of testosterone are synthesized by
Conversion of DHEA → testosterone
31
Controlled primarily by the 2 stimulating hormone produced by pituitary gland such as FSH and LH
TESTOSTERONE
32
2 stimulating hormone produced by pituitary gland that controls testosterone production
FSH
LH
33
stimulating hormone that acts on the germinal stem cells of male
FSH (Follicle-stimulating hormone)
34
stimulating hormone that acts on the Leydig cells of male (stimulate cholesterol conversion to testosterone)
LH (luteinizing hormone)
35
T/F
Amount of testosterone is affected by some physiologic factors
T
Circadian rhythm, Obesity, Age
36
physiologic factors that affects testosterone amount
Circadian rhythm
Obesity
Age
37
Peak of testosterone levels are seen during
8 am (after waking up)
38
Lowest testosterone levels are seen during
8 pm
39
plasma testosterone of obese individuals
decreased
40
how does age affect testosterone production
gradual testosterone ↓ after 30 y/o = 110 ng/dL/decade ↓
41
For growth & development of male reproductive system
testosterone
42
Reference value of testosterone
3.9–7.9 ng/mL (serum)
43
Transport Protein of testosterone (w/ %)
Albumin (50%)
Sex Hormone-Binding Globulin (45%)
44
T/F
Transport protein measurement in male is essential
because binding proteins conc. can determine
testosterone level
T
↑ SHBG = ↑ testosterone
45
T/F
Free testosterone level can be measured in lab
F
46
Conditions under Hypergonadotropic Hypogonadism (Testosterone)
Klinefelter’s Syndrome (XXY)
5-reductase Deficiency
Myotonic Dystrophy
Sertoli cell-only deficiency/germ cell aplasia
Testicular Injury and Infection (mumps orchitis)
Testicular Feminization Syndrome
47
What type of hypogonadism is Hypergonadotropic Hypogonadism (Testosterone)
Primary hypogonadism
48
Hormone levels in Hypergonadotropic Hypogonadism (testosterone)
Low testosterone (stimulates FSH/LH production)
Elevated FSH/LH
49
Condition with Impaired sperm production → infertility/sterility
Hypergonadotropic Hypogonadism (testosterone)
50
Male individual with 3 sex chromosomes
Klinefelter’s Syndrome (XXY)
51
Presence of XX (female chromosomes) in males
Klinefelter’s Syndrome (XXY)
52
Normal 23rd pair of chromosomes in male
XY
53
Manifestations of Klinefelter’s Syndrome (XXY) due to presence of female chromosome (XX)
small firm testicles
gynecomastia (enlarged breast)
azoospermia (presence of semen with no sperm cell)
54
Condition with ↓ dihydrotestosterone
5-reductase Deficiency
55
Manifestation of 5-reductase Deficiency
Physical development similar to female phenotype
Cryptorchidism (presence of ambiguous/ undetermined genitalia)
56
Cryptorchidism is seen in what condition
5-reductase Deficiency
a Hypergonadotropic Hypogonadism (testosterone)
57
Characterized by muscle dystonia and testicular failure (esp. at 4th decade of life)
Myotonic Dystrophy
58
involuntary muscle contraction
Muscle dystonia
59
Testicular failure in myotonic dystrophy usually occurs during this period of life
4th decade of life
60
aka Sertoli cell-only deficiency
germ cell aplasia
61
reason of lacking germ cell in Sertoli cell-only deficiency
Aplasia – no cell growth → lack of germ cell
62
Biopsy of small testis of this condition presents an absence of spermatozoa
Sertoli cell-only deficiency/germ cell aplasia
63
Manifestations and hormone levels in Sertoli cell-only deficiency/germ cell aplasia
small testis
azoospermia
↑ FSH
N/↓ - testosterone
64
Example of Testicular Injury and Infection
Mumps orchitis
65
scrotum inflammation due to mumps infection
Mumps orchitis
66
mechanism of how mumps can cause testicular injury or infection
parotitis/mumps (beke) in males → mumps migrates to scrotum, causing inf. → infertility
67
Most severe form of androgen resistance
Testicular Feminization Syndrome
68
testosterone level in Testicular Feminization Syndrome
Normal
69
Target tissue does not react in response to testosterone (resistance) – NO RECEPTORS
Testicular Feminization Syndrome
70
Manifestation of Testicular Feminization Syndrome
Female-like genitalia w/ intraabdominal testis
71
Hormone levels in Hypogonadotropic Hypogonadism (Testosterone)
Low testosterone
Low/N FSH or LH
72
Conditions under Hypogonadotropic Hypogonadism (testosterone)
Kallman’s Syndrome
Hyperprolactinemia
Type 2 Diabetes
30 y/o age
Opioid use
Pituitary Disease
Obstructive Sleep Apnea
73
Manifestation of hypogonadism at puberty
Kallman’s Syndrome
74
has a manifestation of Red-green color blindness
Kallman’s Syndrome
75
has a manifestation of anosmia (a cerebral dysfunction)
Kallman’s Syndrome
76
Manifestations of Kallman’s Syndrome
Cleft palate/lip
Red-green color blindness
Deafness
Cerebral dysfunction: anosmia (inability to smell; impaired olfactory sensors)
77
GnRH inhibitor that leads to Hypogonadotropic Hypogonadism (testosterone)
PRL
Opioid (narcotics)
78
mechanism why hyperprolactinemia causes Hypogonadotropic Hypogonadism (testosterone)
↑ PRL inhibits FSH/LH production →hypogonadism
PRL – GnRH inhibitor
79
Principal adrenal androgen
Dehydroepiandrosterone (DHEA)
80
Weak adrenal androgen must be converted to a more
potent androgen --> DHEAS
Dehydroepiandrosterone (DHEA)
81
Used as valuable assessment for adrenal cortex function
Dehydroepiandrosterone (DHEA)
82
Most potent female hormone
ESTROGEN
83
Arises through structural alteration of testosterone molecule
ESTROGEN
84
Promote breast, uterine, and vaginal development
ESTROGEN
85
Types of Estrogen
Estrone (E1)
Estradiol (E2)
Estriol (E3)
86
Most abundant estrogen form in post-menopausal women
Estrone (E1)
87
Most potent estrogen
Estradiol (E2)
88
Principal estrogen form
Estradiol (E2)
89
Used to assess ovarian function
Estradiol (E2)
90
Estradiol level in menopausal women?
Estradiol level in pre-menopausal women?
↓: menopausal women
↑: pre-menopausal women
91
Estrogen form found in maternal urine
Estriol (E3)
92
Fetoplacental viability marker
Estriol (E3)
93
Down Syndrome marker (others: AFP, hCG)
Estriol (E3)
94
metabolites of intraovarian testosterone conversion
E1 & E3
95
Progesterone is ONLY produced by
corpus luteum
96
Prime secretory product of the ovary
PROGESTERONE
97
Dominant hormone responsible for the luteal phase
PROGESTERONE
98
Prepares the endometrium for embryo implantation
PROGESTERONE
99
Single best hormone to determine whether ovulation has occurred
PROGESTERONE
100
What happens when progesterone is deficient
failure to embryo implantation (miscarriage)
101
cycle of shedding of uterine lining from the previous cycle among non-pregnant women (no point of start and point of end)
Menstruation
102
2 phases of menstruation
Follicular phase
Luteal phase
103
Starts at the onset of menstruation (1st day of menstruation occur when luteal phase ends)
Follicular phase
104
Menstrual phase that lasts for 14 days
Follicular phase
105
Involves ↑ FSH = ↑ estrogen (positive feedback system) = ↑ LH (LH surge)
Follicular phase
106
Event that occur in the 14th day of follicular phase
LH surge
107
Starts 36 hrs after LH surge
Luteal phase
108
↑ LH will stimulate ovulation in this phase
Luteal phase
109
↑ LH will stimulate ovulation (release of ovum from the ovary) in luteal phase causes?
luteinization of corpus luteum
110
what happen when there is NO fertilization
Shedding of thickened endometrium – NO embryo is implanted
111
what happen when there is fertilization
↑ hCG secreted by placenta
pregnancy test sample: urine
112
Shedding of endometrium is due to this hormone
↑ progesterone
113
Occur 14 days after ovulation at 28th day
Shedding
114
Lasts for 3-5 days
Shedding
115
first day of mens (start of follicular phase; end of luteal phase)
Shedding
116
T/F
Shedding occur for 3-5 days but does not mean that it is the end of follicular phase (lasts for 14 days)
T
117
T/F
Few days after menstruation, female is fertile
T
LH surge presence → ovulation presence
118
Menstrual Cycle Abnormalities
Amenorrhea
Oligomenorrhea
Menorrhagia
119
Absence of menstruation
Amenorrhea
120
Primary Amenorrhea occurs during this age
16 y/o
121
occurs when women had 1 menstrual cycle followed by absences of menstruation for 3-6 mos
Secondary Amenorrhea
122
Infrequent irregular menstrual bleeding
Oligomenorrhea
123
Interval betw 2 mens in Oligomenorrhea?
what is the normal interval?
35-40 days
Normal: 28 days
124
Menstruation that occurs for >7 days
Menorrhagia
125
Excessive shedding
Menorrhagia
126
What is the defect when there is Hypergonadotropic Hypogonadism (female hormones)
ovaries (primary hypogonadism)
127
hormone levels in Hypergonadotropic Hypogonadism (female hormones)
Low female hormone
↑ FSH
Normal/↑ LH
128
Conditions under Hypergonadotropic Hypogonadism (female hormones)
Menopause
Premature ovarian failure
Turner’s syndrome (X ) or (X, partial X)
129
physiologic event among female where menstrual cycle stops
Menopause
130
Menopause occurs at this age range
45-55 y/o (American women)
131
Genetic defect (one X or X with partial X chromosome)
Turner’s syndrome
132
Hypogonadotropic Hypogonadism (female hormones) is aka? reason?
Gonadotropin deficiency
FSH and LH are gonadotropins
133
category of Hypogonadotropic Hypogonadism (female hormones)
Secondary hypogonadism
134
Low female hormone due to low gonadotropins
Hypogonadotropic Hypogonadism/Gonadotropin deficiency
135
Conditions under Hypogonadotropic Hypogonadism/Gonadotropin deficiency
Anorexia nervosa
Runner’s amenorrhea
Prolactinoma
Athlete’s triad
136
Hypogonadotropic hypogonadism that results to weight loss
Anorexia nervosa
*female hormones
137
Associated with females who undergo intense physical exercise → leads to absence of menses
Runner’s amenorrhea
*Hypogonadotropic hypogonadism (female hormones)
138
mechanism of how prolactinoma causes Hypogonadotropic hypogonadism (female hormones)
GnRH inhibitor → ↓ FSH and LH
139
Included in Athlete’s triad
Amenorrhea
Eating disorder
Osteoporosis
140
aka Polycystic Ovarian Syndrome (PCOS)
Enlarged ovaries
141
Former name of PCOS
Stein-Leventhal Syndrome
142
Common among female characterized by multiple ovarian cysts (70% of patients)
Polycystic Ovarian Syndrome (PCOS)/Enlarged ovaries
143
T/F
NOT all have ovarian cysts (30% of patients) in PCOS
T
144
Associated with infertility and other menstrual irregularities
Polycystic Ovarian Syndrome (PCOS)/Enlarged ovaries
145
T/F
PCOS individuals are often overweight
T
146
T/F
PCOS is irreversible
F
Reversed with weight loss, increased physical activity, Metformin
147
Polycystic Ovarian Syndrome (PCOS)/Enlarged ovaries is reversed with?
Weight loss
Increased physical activity
Metformin
148
antidiabetic drug for PCOS? how does it affect PCOS?
Metformin
acts as insulin sensitizer (↑ cell sensitivity to insulin) since PCOS individuals have insulin resistance
149
Mechanism why PCOS often leads to virilization and inhibits ovulation
PCOS individuals have insulin resistance (resembles Type 2 DM). Therefore, INCREASED insulin
↑ insulin = ↑ testosterone
High testosterone level leads to virilization (hirsutism) & inhibits ovulation
150
Excess hair along the midline of the female body
Hirsutism
151
Hirsutism is caused by increased levels of
androgens
152
used to diagnose hirsutism by assessing 9 areas of the body
Ferriman-Gallwey Scale
153
Ferriman-Gallwey Scale specifically assess
Hair thickness
Hair pigmentation
154
9 areas of the body assessed by Ferriman-Gallwey Scale
1. Lip
2. Chin
3. Side burns
4. Neck
5. Chest
6. Abdomen
7. Upper back
8. Lower back
9. Thighs
155
Scoring of Ferriman-Gallwey Scale
0 - 4
156
scoring if there is hirsutism using Ferriman-Gallwey Scale
>8
