prolactin

Mainly controlled by inhibition, i.e. damage to hypothalamus → increase in production

Net effect: mammary gland development and milk production
Secreted from Anterior pituitary (synthesis: hypothalamus)
Stimulus
Inhibition Prolactin inhibitory hormone/dopamine
Site of action Breasts
Action (function) Milk production

Because prolactin inhibitory hormone is kinda the same as dopamine, anything that changes dopamine will also affect prolactin
Hence:

  • dopamine antagonists (e.g. antipsychotics) = more prolactin = galactorrhea, amenorrhea, gynaecomastia
  • dopamine agonists = inhibits prolactin secretion (useful if this is pathologically increased, for example in acromegaly)