Pathology and Physiology Flashcards
What is the other name for the anterior pituitary?
Adenohypophysis
Where is the anterior pituitary derived from?
Rathke’s pouch in the roof of the developing mouth
Where are stimulator and inhibitor hormones released from the hypothalamus absorbed first?
Capillaries in the hypothalamus base
What are the two groups of hormones that the anterior pituitary secretes?
Trophic and non-trophic
What are the trophic hormones secreted from the anterior pituitary?
TSH, ACTH, LH and FSH
Where does TSH act?
Thyroid glands
Where does ACTH act?
Adrenal glands
Where do LH and FSH act?
Reproductive glands
What type of cell (generally) produces trophic hormones in the anterior pituitary?
Basophils
What is the name of the type of basophil which secretes TSH?
Thyrotroph cells
What is the name of the type of basophil which secretes ACTH?
Corticotroph cells
What is the name of the type of basophil which secretes LH and FSH?
Gonadotrophs
What are the non-trophic hormones released by the anterior pituitary?
GH and prolactin
Where does GH act?
All body parts
Where does prolactin act?
Mammary glands
What type of cell (generally) produces non-trophic hormones in the anterior pituitary?
Acidophils
What is the name of the type of acidophil which secretes GH?
Somatotrophs
What is the name of the type of acidophil which secretes prolactin?
Mammotrophs
Apart from basophils and acidophils, what other type of cell is found in the anterior pituitary?
Chromophobes
What is the other name for the posterior pituitary gland?
Neurohypophysis
Where does the posterior pituitary arise from?
It is an extension of neural tissue
What does the posterior pituitary consist of?
Modified glial cells and axonal processes
Where does the posterior pituitary grow from and where does it end up?
Grows down from the brain and remains connected to the hypothalamus via the pituitary stalk
Which hormones are secreted from the posterior pituitary?
ADH and oxytocin
Where are ADH and oxytocin synthesised?
Nerve cells within the hypothalamus
What happens to the level of extracellular fluid when hormones are released from the posterior pituitary?
It rises
Where does ADH act?
Urine collection channels in the kidneys
Where does oxytocin act?
Mammary glands and smooth muscles above the uterus
What are the causes of anterior pituitary hyper function?
Pituitary adenoma or carcinoma
What are the causes of anterior pituitary hypo function?
Surgery Radiation Sudden haemorrhage Ischaemic necrosis (Sheehan's) Tumour extending into the sella turcica Infiltrative inflammatory conditions
What are the causes of posterior pituitary hyper function?
SIADH, ectopic ADH production, primary disorder in the pituitary
What is the cause of posterior pituitary hypofunction?
Diabetes insipidus
