anatomy - ANS and hypothalamus Flashcards
What are the limbic, endocrine and ANS systems associated with?
limbic - emotion
endocrine - homeostasis, sleep, reproduction
NAS - sexual arousal
What’s the location of the hypothalamus? It’s part of the mesencephalon T/F?
FALSE, part of the diencephalon, around third ventricle
Explain the connectivity between the hypothalamus, limbic system, ANS, endocrine system, and cortex
endocrine hypothalamus
hypothalamuslimbic system
hypothalamusANS
hypothalamus–histamine,orexin,GABA->cortex
which system is the hypothalamus a part of?
What are 2 other parts of the diencephalon
limbic system
diencephalon = thalamus, hypothalamus, epithalamus, subthalamus
how is the hypothalamus connected to the hippocampus? To the brain stem? Thalamus?
What does the hypothalamus do?
hippocampus connected via fornix
brain stem connected via medial forebrain bundle (from oldfactory bulb)
thalamus connected via mammilothalamic
Through limbic system = deals with emotion regulation and gets regulatory input for the ANS
what nerves connect the hypothalamus in general? The PS and S innervation ones
splanchic (sympathetic)
vagus (parasympathetic)
Thermoregulation
Which nerve bundle is involved when it’s too hot? Too cold?
Too hot - anterior hypothalamus neurons
Too cold - posterior hypothalamus neurons
which nuclei in the hypothalamus is involved in water balance?
supraoptic and paraventricular nuclei
Explain the mechanisms of hunger
What hormone promotes hunger? Satiety?
When you eat, stomach distends, which signals to hypothalamus
As stomach fills, hormones secreted via endocrine system to act on hypothalamus to indicate satiety
If stomach empty, stomach releases Ghrelin to trigger appetite.
Hunger - ghrelin
Satiety - CCK, PYY, GLP1
What’s the neuronal mechanism of hunger suppression?
stretch receptors send signals through vagus nerve to hypothalamus to suppress hunger
what is orexigenic and anorexigenic?
we think mediobasal hypothalamus contains both:
orexigenic (anabolic)
anorectic (catabolic)
neurons!
Mediobasal hypothalamus contains orexigenic neurones on one side, and anorectic neurones on the other. T/F?
FALSE - no complete separate regions, one structure with two functionalities
Which neuropeptides stimulates food intake? Which suppress?
NPY and AGRP stimulate food intake
POMC inhibit food intake
which nucleus in hypothalamus drives the circadian rhythm?
suprachiasmatic nuccleus
What’s a zeitgeber?
circadian rhythm persists when deprived of a zeitgeber (signal)
biggest zeitgeber is light
