Lactation and Prolactinomas Flashcards
Where is prolactin produced?
In the anterior pituitary by the lactotroph cells
Effect of dopamine on prolactin release
prolactin release inhibited
Effect of 5HT (serotonin), TRH, oxytocin on prolactin release
Prolactin release stimulated
Presentation of HYPERPROLACTINAEMIA in women
- oligo / amenorrhoea
- risk osteoporosis (due to lack of oestrogen)
- galactorrhoea
- subfertility
Presentation of HYPERPROLACTINAEMIA in men
-Erectile dysfunction
reduced libido
-visual symptoms
headaches
hypopituitarism
-Present later
Galactorrhoea / gynaecomastia RARE
Causes of HYPERPROLACTINAEMIA
- physiological
- Hypothalamic-pituitary disease
- drugs (common!!)
- stress
- other (PCOS, liver cirrhosis)
Cabergoline
Dopaminergic drugs used to treat hyperprolactinaemia
Stages of lactogenesis
secretory initiation
- progesterone
- in pregnancy
- colostrum
secretory activation
- low progesterone/oestrogen
- raised prolactin
What is galactopoiesis?
Lactation
via Positive feedback loops
-nipple stimulation=regular milk removal
Why can lactation be an effective form of contraception?
high prolactin= low GnRH, low LH and FSH,
low oestrogen/testosterone
Where is oxytocin synthesised?
synthesised in hypothalamic magnicellular neruones
i.e supraoptic nucleus
paraventricular nucleus
What is oxytocin responsible for?
+ uterine myometrial contraction at birth
+ smooth muscle activation in breast
‘myoepithelial contraction’
+ milk let-down path
Drugs that raise prolactin?
Antidepressants and antipsychotics
Drugs used for nausea & vertigo
Phenothiazines
Metoclopramide
Domperidone
how would you treat tumour below 1 cm?
microPRLomas
can take COCP/HRT if fertility not required
can discontinue treatment in pregnancy
NFA MANAGEMENT
can present as prolactinoma
compression of stalk
dopaminergic drugs
surgery and radiotherapy
Transphenoidal hypophysectomy
