Acidophils, basophils and chromophobes, each producing different hormones
Expansion
Anterior pituitary (adenohypophysis), of ectodermal origin from Rathke pouch:
- Acidophils (pink): somatotrophs (growth hormone) and lactotrophs (prolactin)
- Basophils (blue): corticotrophs (ACTH), thyrotrophs (TSH), gonadotrophs (FSH and LH)
- Chromophobes: pale, degranulated or inactive cells
A useful aide memoire is that the glycoprotein hormones (TSH, FSH, LH) plus ACTH come from basophils, while the simple peptide hormones (growth hormone, prolactin) come from acidophils.
Posterior pituitary (neurohypophysis) is neural tissue: unmyelinated axons from the hypothalamus, pituicytes (specialised glia), and Herring bodies, which are dilated axon terminals storing hormone. It contains no secretory cell bodies.
Blood supply: the anterior lobe receives blood almost entirely through the hypophyseal portal system rather than directly, which is why stalk section causes anterior lobe failure and why prolactin uniquely rises (losing dopamine inhibition) while everything else falls.
Modern classification of adenomas uses immunohistochemistry for the specific hormone and transcription factors rather than staining affinity.