Prolactin

Question 1

Where is prolactin produced?

Answer 1

Anterior pituitary gland, Decidualized endometrium, Myometrium

Question 2

What is the main function of prolactin?

Answer 2

lactogenesis

Question 3

True or false: In pregnancy prolactin is also responsible for amniotic fluid regulation?

Answer 3

True

Question 4

What two hormones increase secretion of Prolactin from the anterior pituitary?

Answer 4

estrogen and thyroid releasing hormone

Question 5

Prolactin stimulates _____ and _____

Answer 5

Breast growth and lactation

Question 6

During pregnancy, lactation is inhibited by _____

Answer 6

Progesterone

Question 7

What hormone triggers ejection of milk/let down during lactation?

Answer 7

oxytocin

Question 8

Oxytocin release is triggered by ____.

Answer 8

Nipple stimulation

Question 9

Failure to lactate within 7 days after delivery may be the first sign of what syndrome?

Answer 9

Sheehan’s syndrome

Question 10

What causes Sheehan’s syndrome?

Answer 10

Infarct of the pituitary gland leading to hypopituitarism

Question 11

What is the main hormone responsible for blocking the secretion of prolactin?

Answer 11

Dopamine

Question 12

Galactorrhea is due to increased _______

Answer 12

Prolactin

Question 13

What percent of women with Galactorrhea will have elevated prolactin?

Answer 13

33%

Question 14

What medications can cause Galactorrhea?

Answer 14

Dopamine receptor blockers ( Antipsychotics, metoclopramide, SSRIs, TCAs), Dopamine depleting agents (Methyldopa, Reserpine), Dopamine release inhibitors (Opiates, Cimetidine)

Question 15

What types of tumors can cause Galactorrhea?

Answer 15

Prolactinoma in the pituitary gland

Question 16

What other symptoms are associated with Macroprolactinomas?

Answer 16

visual field defects, headaches

Question 17

What other metabolic syndrome can cause galactorrhea and by what mechanism?

Answer 17

Hypothyroidism, increased TRH

Question 18

Hypothalamic lesions that block or compress the stalk cause galactorrhea by what mechanism?

Answer 18

Block delivery of dopamine to the anterior pituitary

Question 19

Hyperprolactinemia causes what change in the menstrual cycle?

Answer 19

most often causes amenorrhea

Question 20

What is the mechanism of action by which high levels of prolactin interfere with the menstrual cycle?

Answer 20

inhibits pulsatile secretion of GnRH

Question 21

What tests should be performed when evaluating a patient with Galactorrhea?

Answer 21

pregnancy test, serum prolactin

Question 22

What tests should be done if prolactin is elevated?

Answer 22

MRI with gadolinium of brain and pituitary

Question 23

What is the normal level of serum Prolactin in non pregnant state

Answer 23

< 25 ng/ml

Question 24

What is the normal level of serum prolactin in the pregnant state?

Answer 24

400 ng/ml

Question 25

What is the definition of microadenoma

Answer 25

< 1 cm

Question 26

What class of medication are highly effective at treating hyperprolactinemia?

Answer 26

Dopamine agonists

Question 27

What are two examples of dopamine agonists?

Answer 27

Bromocriptine, Cabergoline

Question 28

What is the starting dose of bromocriptine and how should it be titrated?

Answer 28

Start with 2.5mg at bedtime, titrate until menses achieved and prolactin levels normalize

Question 29

what are common side effects of bromocriptine?

Answer 29

nausea, headache, orthostatic hypotension

Question 30

How can bromocriptine be administered to decrease side effects?

Answer 30

vaginally

Question 31

How should microadenomas be managed?

Answer 31

dopamine agonist, repeat prolactin and imaging q 2 years

Question 32

When should you offer surgery for macroadenomas?

Answer 32

With failed medical management and persistent CNS symptoms

Question 33

What is the treatment for a woman at 20 weeks gestation who has bothersome galactorrhea and growth in her microprolactinoma?

Answer 33

Bromocriptine