Hypothalamus / Pituitary Flashcards
The sella turcica houses _
The pituitary
The pituitary has 3 lobes. Which is not found in adults?
Anterior, Intermediate, Posterior
Intermediate
The superior hypophyseal artery connects _ with _. The specific branch making this connection is _
Portal system connecting anterior pit with hypothalamus.
Trabecular artery
What is the significance of the median eminence?
It is a location where hypothalamic hormones are released into the portal system connecting the hypothalamus and pituitary
The blood supply to the posterior lobe of the pituitary is _. What 2 hormones are secreted from nerve terminals in the posterior pit.? Where are they made?
Inferior hypophyseal artery
ADH and oxytosin
Hypothalamus
There are 5 trophic hormones released from the anterior pit. What are the cell types that produce these hormones? hGH ACTH TSH LH/FSH Prolactin
hGH - Somatroph ACTH - Corticotroph TSH - Thyrotroph LH/FSH - Gonadotroph Prolactin - Mammotroph
Dopamine is the same as _
Prolactin inhibitory factor
The most common tumor of the aterior pituiary is _. What is the effect? How can it affect males?
Prolactinoma - too much prolactin secretion, can block LH/FSH in males, leading to infertility
The only tonically inhibited anterior pit. hormone is _
Prolactin
Released in pulses, act on membrane receptors, stimulate release / sythesis of hormone, cause target glycosylation. These are characteristics of _
The hypothalamic releasing hormones
What mediates the ultrashort loop, short loop and long loop feedback?
Ultra - the releasing hormone itself
Short - the Pituitary product
Long - The product of the target cell
Increased protein synthesis, decreased utilization of glucose, increased lipolysis are all effects of _
hGH
The growth promoting effect of GH are mediated by _, AKA _
IGF-1
Somatomedin C
GH directly acts on _ (2) Most other effects are mediated via _
Adipose, Muscle
IGF1
The GH receptor requres _(#) molecules of GH to bind, leading to _. Its activation leads to activation of _
2
Dimerization
STAT
GH is pro-protein synthesis, therefore it _ [increase/decrease] AA transport into the cell.
Increases
GH [ncreases / decreases] lipolysis. It can therefore contribute to insulin resistance
Increase
GH can cause hyperglycemia via to mechanisms. They are _
Increase gluconeogenesis in the liver
Decreased glucose uptake by insulin sensitive cell
Pituitary diabetes is _
Increased blood glucose from GH
Inadequate / no production of insulin from B cells can lead to _
Type 1 diabetes mellitus
What is the effect of GH on bones?
Stimulates the lengthening of long bones
Stimulates the thickening of non-long bones (jaw, skull)
The growth promoting effects of GH are mediated via _
IGF-1 / somatomedin
Of the 3 types of feedback loops, GH is inhibited by _
All three
Somatostatin [promotes/inhibits] GH
Ghrelin (GHRP) [promotes/inhibits] GH
Inhibits
Promotes
