Endocrine - Hormones II (Anterior Pituitary and Thyroid) Flashcards
What is the master control center of the endocrine system?
Hypothalmus
What is the target organ of the hypothalamus?
Pituitary
What stimulates TSH production? Where is it produced?
TRH - thyrotropin releasing hormone
Hypothalmus
What stimulates PRL (prolactin) production? Inhibits it?
PRF - prolactin releasing factor
PIH - prolactin release-inhibiting hormone
What stimulates ACTH production?
CRH - corticotropin releasing hormone
What stimulates both LH and FSH?
GnRH - gonagotropin releasing hormone
What stimulates GH? Inhibits GH?
GHRH - stimualtes
SS - inhibts
What portion of the hypothalamic releasing hormones prevents degredation and lengthens half-life?
Cyclic N-terminal
Are hormones of the anterior pituitary made on demand or made and stored? How are they released
Made and Stored in pre-existing vesicles
Vesicles exocytosed after stimulated by hormones from hypothalamus
What three tissues does GH directly affect? Which tissue does it act on primarily to release IGF1?
Bone, Muscle, Adipose
Liver - primary source of LGF1
What hormones act through the JAK/STAT (nonreceptor tyrosine kinase) pathway? PIGG(L)ET
Prolactin Immunomodulators GH G-CSF Erythropoietin Thrombopoietin
How does the Jak/STAT kinase cascade begin?
Ligand binds to receptor
Receptor dimerizes upon hormone binding
Jaks phosphorylate as a result of dimerization
Jaks phosphorylate intracellular domains
STAT phoshphorylated by intracellular domain
Dimerization of stat and nuclear translocation
What does it mean the TSH, FSH, and LH are all glycoproteins?
All are glycosylated
Which subunit of g-protein receptors are the same? Which subunit is different? What does this allow?
Alpha - same subunit across receptors
Beta - different
Beta confers biologic activity of receptor
Is the Beta subunit active in the absence of the alpha-subunit?
No