Unit 10 - Hyperprolactinemia
Hyperprolactinemia Symptoms - Women
- Galactorrhea (increased milk prod.) - Anovulatory Amenorrhea (absence in ovulation and menses)
Hyperprolactinemia Symptoms - Men
- Gynecomastia (breast enlargement) - Erectile Dysfunction
Hyperprolactinemia Causes - Damage to Hypothalamic-Pituitary Stalk
- contains vessels that connect hypothalamus to pituitary - due to trauma, nearby tumors, brain surgery
Hyperprolactinemia Diagnosis
- detecting high levels of prolactin in blood - Pregnancy check - Brain MRI (look for prolactinoma)
Hyperprolactinemia Causes - Physiologic Hyperprolactinemia
- during preg. and lactation, typically returns to normal after
Hyperprolactinemia Symptoms - Prolactinoma
- headaches + impaired vision (due to pressing on optic nerve)
Prolactin - Women
- increased levels of estrogen in pregnant women leads to increased prolactin - stimulates alveolar cells in breasts (divide + enlarge) - once baby is born, lactogenesis begins
Prolactin Regulation - Breastfeeding women
- inhibits release of gonadotropin-releasing hormone - luteinizing + follicle stimulating hormone decreases estrogen in response
Lactotroph Cells
- on anterior of pituitary - secrete prolactin
Hyperprolactinemia Causes - Prolactinoma
- pituitary adenoma, benign tumor of lactotroph cells - increased amt. of prolactin - Hypothyroidism (Hypothalamus tries to increase thyroid hormones by increasing Thyrotropin Releasing Hormone, increased prolactin levels)
Prolactin - Men
- stimulates testosterone production
Hyperprolactinemia Treatment
- varies on underlying cause - Dopamine Agonists (Bromocriptine) - Prolactinoma >> Surgery - Hypothyroidism >> Replacement thyroid hormones
Prolactin Regulation - Regular people
1. Hypothalamus secretes dopamine (prolactin inhibiting factor) OR 2. Secretes Thyrotropin Releasing Hormone (prolactin releasing hormone) stimulates prolactin release, looping back to first step to force negative feedback.
Hyperprolactinemia Causes - Medication
[Dopamine Antagonists] - remove inhibition on lactotroph cells [Estrogens] - stimulate lactotrophs to produce prolactin
