QUESTIONS AND ANSWERS
Function of the hypothalamus
respond to deviations in set points (body temperature, blood volume, osmolality, satiety, fat
content, body weight)
set points that can change:
body fat content
body weight
satiety
set points that don't really tolerate change:
body temp
blood volume
osmolality
coordinated responses to set point deviations include
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, nervous system: leads to behavior changes (i.e. increase how much you eat if your satiety set
point increases)
endocrine system: hormone release to restore body back to homeostasis
intravascular volume loss leads to
activate sympathetic nervous system → increase HR to maintain CO + vascular smooth muscle
contraction to maintain BP
increasing osmolarity leads to
dehydration → thirst response → vasopressin release (aka ADH)
vasopressin function:
causes kidney to excrete more sodium and retain more water
3 original transcription factors in pituitary
PITX2, HESX1, LHX4
activation of these transcription factors creates more transcription factors that allows for the
differentiation of pituitary cell types
example:
activate PITX2, HESX1, LHX4 → activate PTIT and NEUROD1 → production of ACTH
ACTH
adrenocorticotropin hormone
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