To eat or not to eat-Valencik Flashcards
What is anorexigenic?
suppresses appetite
What is orexigenic?
increases appetite
What is satiation?
cessation of hunger
What is satiety?
sensation of being full
What are enteroendecrine cells?
endocrine cells of the GI tract and pancreas
What are incretins?
gut hormones that stimulate insulin secretion
What are oxyntic cells?
gastric parietal cells that release gastric aid
What are orexins?
hormone that regulates sleep and appetite
What are the adiposity signals?
- insulin
- adiponectin
- leptin
What are the gut hormones?
- PYY
- OXM
- Ghrelin
- PP
- GLP-1
- CCK
What are the long term signals for energy homeostasis?
Leptin
Insulin
What does leptin do?
- secreted in proprotion to fat stores
- eat less, less body fat, less leptin is produced
- however body adapts by minimizing energy usage and increasing appetite
What does insulin do?
decreases appetite
What are the short term signals in energy homeostasis?
GI tract hormones (size of meals, number of meals) Ghreline (hunger) CCK (full) PYY (full) Gastric emptying (full)
Their are neurons and neurotransmitters in the (blank) that stimulate or inhibit feeding
hypothalamus
What are the neural centers that regulate food intake?
Hypothalamus
- lateral nuclei (LN)
- ventromedial nuclei (VMN)
- Paraventricular nuclei (PVN)
- Dorsomedial nuclei (DMN)
- Arcuate nuclei (ARC)
The lateral nuclei (LN) is the (blank) center of the brain
feeding
When LN is stimulated what happens?
hunger increases a lot-> hyperphagia
What happens if you destroy your LN?
no urge to eat (inanition)
-weight loss, muscle weakness, and decreased metabolism
What is the satiety center?
Ventromedial nuclei (VMN)
When the VMN is stimulated, what happens?
no urge to eat
refusal to eat (aphagia)
What happens if the VMN is destroyed?
you have a voracious appeptide and continued eating can lead to obesity
What part of the brain is this:
lesions lead to excessive eating
paraventricular nuclei (PVN)
What part of the brain is this:
lesions depress eating
Dorsomedial nuclei (DMN)
What part of the brain is this:
Site where multiple hormones released from GI and adipose tissue converge to regulate eating and energy consumption
Arcuate nuclei (AN)
What are the 2 distinct types of neurons in the arcuate nuclei?
Anorexigenic
Orexigenic
What are the anorexigenic neurons and what do they do?
POMC/CART
pro-opiomelanocortin/ cocaine-and amphetamine-regulated transcript (CART)
These neurons produce alpha-melanocyte-stimulating hormone (a-MSH) and CART peptide
What are the orexigenic neurons and what do they do?
AgRP/NPY these produce agouti-related protein (AgRP) neuropeptide Y (NPY)
Insulin, leptin and CCK cause you to feel full or hungry?
full
Ghrelin causes you to feel full or hungry?
hungry
(blank) neurons release alpha-MSH leading to the activation of melanocortin MCR-3 and MCR-4 receptors on the PVN
POMC/CART
When POMC/CART neurons are releasing alpha-MSH, what else is being released simultaneously?
CART peptide is released and binds to an unknown receptor.
What does POMC/CART stimulate?
the PVN regulation pathways that inhibit eating and stimulate energy expenditure (anorexigenic control)
Additional (blank) can augment or inhibit the POMC/CART function
peripheral peptide hormones
Orexigenic neurons release (Blank) and (blank) in response to low energy stores.
AgRP
NPY