Pituitary Gonadal

Question 0

Sex hormone binding globulin

Answer 0

Binds testosterone

Increases in aging, cirrhosis, estrogen, anticonvulsant, HIV, decreased TSH

Decreases in nephrotic syndrome, increased TSH, androgens, obese

Question 1

Sertoli cells

Answer 1

Secrete sperm

Question 2

Androgen deficiency signs

Answer 2

Decreased libido
Decreased spontaneous erection
Gynecomastia 
Loss of body hair 
Hot flashes

Question 3

Prolactin

Answer 3

Inhibits LH, produces milk

Measure PRL when hypogonadism suspected

Stimulated by TRH
Inhibited by dopamine

Treat with dop agonist: bromocriptine, cabergoline

Question 4

Spermatogenesis

Answer 4

Requires hCG or LH, FSH

Give HCG (LH mimic) and FSH in congenital 2nd) hypogonadism

Question 5

Androgen deficiency

Answer 5

Different among stages

Genital development
Muscles, voice

Adult: sexual dysfunction, osteoporosis
Gynecomastia

Question 6

Primary hypogonadism

Answer 6

Low testosterone

High LH&FSH l, long arms and legs

From testicles, klinefelter 47XXY

Tx: testosterone

Question 7

Secondary hypogonadism

Answer 7

Low T, low LH/FSH

Hyperprolactinemia low GnRH /LH
Congenital lack GnRH

Kallman

From pituitary,
Tx: HCG (LH analog) or testosterone

Question 8

Infertility

Answer 8

Many take androgen/ testosterone which blocks LH has and FSH

Tx: clomen (releases LH&FSH)

Question 9

Androgen abuse

Answer 9

Suppress testicular function, sperm production

Gynecomastia

Decrease HDL increase LDL

Hepatotoxicity

Question 10

Primary Ovarian insufficiency

Answer 10

Gonadal dysgenesis: ovaries lack follicles and lack estrogen

45 XO turner
short stature, osteoporosis

Low E2 increases FSH/LH

Question 11

Menopause Estrogen therapy contraindications

Answer 11

Estrogen dependent tumors

Liver disease

Thromboembolic disease

Use progesterone if intact uterus to oppose estrogen

Question 12

Secondary ovarian insufficiency - hyperprolactinemia

Secondary amenorrhea

Answer 12

Alters pulsatile GnRH

Decreased GnRH receptors
Decreased FSH, LH

TRH stimulates prolactin release
Lack of dopamine stimulates PRL

Question 13

Ovarian hyperfunction- hyperandrogenism PCOS

Answer 13

Polycystic ovary syndrome

Increase LH/FSH (>2)
androgen secretions (T>200)

Hirsutism, acne, insulin resistance

Question 14

Adrenal Hyperandrogenism

Answer 14

Impaired cortisol synthesis
21 hydroxylase deficiency

More downstream androgen

Give hydrocortisone for neg feedback on pituitary ACTH

Fludrocortisone

Question 15

ADH (vasopressin)

Answer 15

Secreted forms posterior pituitary

Vasoconstriction: Gaq

water retention: Gas

Regulated by osmolality and plasma volume

Question 16

Anterior pituitary GPLAT

Answer 16

ACTH
TSH
Growth hormone
Prolactin 
LH/FSH

Question 17

Growth hormone

Answer 17

Bone growth, density
Muscle mass
Tumor promotion
Protein synthesis

Lipolysis

Simulated by GHRH, dopamine, 5HT
Inhibited by somatostatin, IGF1

Question 18

GH excess

Answer 18

Gigantism, acromegaly

Give bromocriptine dop agonist
Somatostatin, octreotide
GH receptor antagonist: pegvisomant

Question 19

GH deficiency

Answer 19

Give GH replacement therapy
Sermorelin, somatotropin

Mercasermin IGF1 for laron, pygmies

Question 20

Oxytocin

Answer 20

Spikes during labor causing uterine contractions

Lets milk out of breast
Bonding, maternal behavior

Gaq IP3 Ca muscle contraction

Agonist induce labor: Pitocin
Antagonist suppress premature labor: tractocile

Question 21

LH

Answer 21

Forms corpus luteum in Female

Produces testosterone in male

Question 22

FSH

Answer 22

Initiates ovulatory cycle

Stimulates Sertoli cell spermatogenesis

Question 23

LH FSH excess

Answer 23

Testicular failure, Turner syndrome

Early puberty, irregular cycle, infertility

Tx: GnRH antagonist, continuous GnRH agonist (downregulation)

Gonadorelin acetate for infertility

Question 24

LH/FSH deficiency

Answer 24

Delayed puberty

Pulsatile GnRH agonist: leuprolide, nafarelin

Question 25

Testosterone rate limiting step

Answer 25

LH induced cholesterol conversion to Pregnenolone

Question 26

Androgen cortisol balance

Answer 26

Excess androgen loss of growth potential

Excess cortisol decrease growth, increase BPH Cushing’s

Question 27

Hyperprolactinemia

Answer 27

May be due to hypothyroidism or dopamine deficiency