Hyperprolactinemia

Question 1

Describe the release of prolactin

Answer 1

Prolactin is released from the anterior pituitary by LACTOTROPH cells, under stimulation of oestrogen, nipple stimulation or TRH.

Question 2

What three factors stimulate prolactin?

Answer 2

Oestrogen
Thyrotrophin releasing hormone
Nipple sucking

Question 3

Which hormone inhibits prolactin release?

Answer 3

Dopamine

Question 4

Where is dopamine released and how does it get to the lactotroph cells?

Answer 4

Released via neurons in the arcuate nucleus, and gets to the lactotroph cells in the anterior pituitary via the hypophyseal system.

Question 5

What does TRH stand for?

Answer 5

Thyrotrophin releasing hormone

Thyrotrophin = TSH (thyroid stimulating hormone)

Question 6

What are the effects of prolactin?

Answer 6

Milk production in the lobules of the breast tissue

GnRH inhibition so downstream LH and FSH inhibition

Question 7

How is prolactin cleared?

Answer 7

In the urine

Question 8

Give some broad causes of hyperprolactinemia

Answer 8

Drug induced dopamine inhibition

Hypothalamic-pituitary conditions

Hypothyroidism

Renal failure

Chest wall trauma

Question 9

Name some drugs that cause hyperprolactinemia and briefly explain how they cause it

Answer 9

Antipsychotics (dopamine inhibition)
Tricyclic antidepressants

Antiemetics e.g. metaclopramide

Opiods

Oral contraceptives

Methyldopa