Hypopituitarism Flashcards
Name the 5 main cell types of the anterior pituitary gland
Somatotrophs Thyrotrophs Lactotrophs Gonadotrophs Corticotrophs
Name the 6 main hormones released from the anterior pituitary
Growth hormone (somatotrophin)
TSH (thyroid stimulating hormone, thyrotrophin)
Prolactin
LH/FSH (luteinising hormone/follicle stimulating hormone)
ACTH (adrenocorticotrophic hormone, corticotrophin)
What’s the main difference in tissue type between the anterior and posterior pituitary gland?
The anterior pituitary comprises endocrine tissue whereas the posterior pituitary is composed of neural tissue
What does the anterior pituitary gland need to release hormones that the posterior pituitary does not? Why?
The anterior pituitary needs a blood supply to release its hormones whereas the posterior pituitary does not. This is because the posterior tissue is made of neural tissue vs anterior pituitary’s endocrine tissue.
What hormone do the somatotrophs secrete?
GH (somatotrophin)
What hormone do the lactotrophs secrete?
Prolactin
What hormone do the thyrotrophs secrete?
TSH (thyroid stimulating hormone, thyrotrophin)
What hormones do the gonadotrophs secrete?
LH, FSH
What hormone do the corticotrophs secrete?
ACTH (adrenocorticotrophic hormone, corticotrophin)
How do hypothalamic-releasing/inhibiting factors reach the anterior pituitary?
They travel in the hypothalamic-pituitary portal circulation (and down the pituitary stalk)
What do hypothalamic-releasing/inhibiting factors do in regards to the anterior pituitary?
Regulate anterior pituitary hormone production
What glands do LH/FSH stimulate?
Gonads - testes + ovaries
What gland does TSH stimulate?
Thyroid gland
What gland does ACTH stimulate?
Adrenal gland (cortex)
What is the main action of LH/FSH on the gonads?
Stimulate the release of sex hormones (testosterone, oestrogen)
What is the main action of TSH on the thyroid gland?
Stimulate the release of thyroxine
What is the main action of ACTH on the adrenal cortex?
Stimulate the release of cortisol
What are the three main glands affected in anterior pituitary failure?
Thyroid
Adrenal cortex (cortisol)
Gonads
What are the two main groups of disease that could cause failure of the thyroid, adrenal cortex or the gonads?
Primary disease
Secondary disease
Differentiate primary and secondary anterior pituitary failure.
Primary - gland itself fails
Secondary - no/reduced signals from hypothalamus or anterior pituitary gland
What is primary hypothyroidism?
Low thyroid hormone levels due to destruction of the thyroid gland
What is the main problem in primary hypothyroidism?
Destruction of the thyroid gland resulting in reduced thyroid hormone production