Pituitary Gland Pathology Flashcards
Location
Inferior to the hypothalamus
Anterior Pituitary
Adenohypophysis
Derived from Rathke;s pouch
Secretes trophic and non-trophic hormones
Trophic Hormones
TSH
ACTH
FSH
LH
Non-trophic hormones
GH
Prolactin
Posterior Pituitary
Neurohypophysis
Extension of neural tissue consists of modified glial cells and axonal processes
Secretes ADH (vasopressin) and oxytocin
Anterior Pituitary (Histology + Hormones)
Islands, cord of cells
Acidophils
- somatotrops =GH
- mammotrophs= Prolactin
Basophils
- corticotrophins = ACTH
- thyrootrophs = TSH
- gonadotrophs = FSH/ LH
Chromophobe
Posterior Pituitary (Histology)
Non-myelinated axons of neurosecretory neurons
Anterior Pituitary Hyperfunction aetiology
Adenoma
Carcinoma
Anterior Pituitary Hypofunction aetiology
Surgery/radiation Sudden haemorrhage into gland Ischaemic necrosis Tumours extending into sella Inflammatory conditions
Posterior Pituitary Common pathology
Diabetes Insipidus
- Lack of ADH secretion
- can lead to life-threatening dehydration
SIADH
- ectopic secretion of ADh by tumours
- primary disorder in pituitary
Pituitary adenoma
Derived from cells of anterior pituitary
Sporadic or associated with MEN1
Micro vs macro adenomas
Microadenomas <1cm
Macroadenomas >1cm
Classification of pituitary adenomas
Classified by cell type/ hormone produced - prolactin -ACTH -FSH/LH - GH (Can produce more than one hormone0
large pituitary adenoma consequences
Visual field defects
pressure atrophy of surrounding normal tissue
Functional Pituitary Adenomas
Prolactinoma
Growth Hormone Secreting
ACTH secreting
