Pathology of Endocrine System 2 Flashcards
Where is the pituitary gland located?
Sella turcica
What is the pituitary gland connected to the hypothalamus by?
Pituitary stalk
What are the 2 distinct components of the pituitary gland?
Anterior pituitary
Posterior pituitary
What is the anterior pituitary also called?
Adenohypophysis
Which componenet of the pituitary gland is the larger?
Anterior pituitary (is 80% of mass)
What does the anterior pituitary secrete?
ACTH
TSH
GH
Prolactin
FSH/LH
What is the secretion of hormones from the anterior pituitary controlled by?
Release factors from hypothalamus
Where does the blood supply to the anterior pituitary come from?
Hypothalamus
What is the posterior pituitary also called?
Neurohypophysis
What does the posterior pituitary secrete?
ADH
Oxytocin
What is the most common cause of pituitary hyperfunction?
Pituitary adenoma (carcinomas are very rare and also some hypothalamic disorders)
What age group does pituitary adenoma usually affect?
35-60 years
Is there a genetic predisposition to pituitary adenoma?
MEN-1
What is the effect of a functioning pituitary adenoma?
- Effects if functioning is hormone excess
- Prolactinoma 20-30%
- Galactorrhoea, menstrual disorders
- GH secreting
- Acromegaly, gigantism
- ACTH secreting
- Cushing’s disease
- Non-functioning 25-30%
- Prolactinoma 20-30%
If a pituitary adenoma is a prolactinoma, what does it cause?
Galactorrhoea
Menstrual disorders
If a pituitary adenoma is a GH secreting, what does it cause?
Acromegaly
Gigantism
If a pituitary adenoma is a ACTH secreting what does it cause?
Cushing’s disease
What can happen if a pituitary adenoma is large?
- If large, can have a mass pressure effect
- Radiographic abnormalities
- Visual field abnormalities
- Elevated intracranial pressure
- Compression damage, such as hypopituitarism
What percentage of pituitary function needs to be los to be considered pituitary hypofunction?
75%
What can cause pituitary hypofunction?
Compression by tumours
Trauma
Infection (rare)
Post partum ischaemic necrosis
What infections can cause pituitary hypofunction?
TB
Sarcoidosis
What are the adrenal glands composed of?
Adrenal cortex
Adrenal medulla
What classification of hormones does the adrenal cortex secrete?
Steroid hormones
What are the 3 layers of the adrenal cortex?
- Zona glomerulosa secretes mineralocorticoids (aldosterone)
- Zona fasciculate secretes glucocorticoids (cortisol)
- Zona reticularis secretes sex steroids
What does the zona glomerulosa secrete?
Minerlocorticoids (aldosterone)
What does the zona fasciculate secrete?
Glucocorticoids (cortisol)
What does the zona reticularis secrete?
Sex steroids
What does the adrenal medulla secrete?
Adrenaline/noradrenaline
What cells are found in the adrenal medulla?
Neuroendocrine (chromaffin) cells