Obesity (and MHS) Flashcards
What is the effect that causes a patient to feel better by merely going to see a doctor, or taking a drug, whether it has a physiological effect or not?
Conditioned response. The placebo effect is an example of a conditioned response.
If a conditioned response proves to not work after a while (there is no physiological effect), and this is repeated numerous time, the patient may unlearn the response. What is this called?
Extinction
From which of the trilaminar disc layers does the GI arise?
Endoderm.
When does the flat endoderm sheet form a tubular gut?
week 4
From what does the gut tube form?
yolk sac.
the newly formed gut tube remains connected to the rest of the disc by mesenteries.
What is the opening at one end of the gut tube called that will form the mouth?
Stomodeum
What is the opening at one end of the gut tube that will form the anal pit?
Proctodeum
What makes up the foregut?
Everything up to the ampulla of Vater in the duodenum.
What makes up the midgut?
From the ampulla of Vater to 2 thirds along the transverse colon.
What makes up the hindgut?
last 3rd of transverse colon,
most of urethra and epithelium of bladder.
How does the stomach form?
Dorsal side grows faster.
Tube rotates to the right 90 deg.
dorsal mesentery becomes greater omentum.
How does the pancreas form?
There are two pancreatic buds: dorsal and ventral, on the duodenum. the duodenum rotates posteriorly so the ventral bud meets the dorsal bud, then they fuse.
What are the three subregions of the hypothalamus wrt appetite?
Lateral.
Ventromedial.
Arcuate nucleus.
What is the stimulation for the ventromedial and lateral hypothalamus wrt appetite?
blood glucose.
What part of the hypothalamus is stimulated by a low blood glucose level?
Lateral
What part of the hypothalamus is stimulated by a high blood glucose level?
ventromedial.
What leptin released by?
Adipocytes. The fatter the person - the more leptin is released.
Where does leptin act and what does it cause?
arcuate nucleus which: decreases AGRP and NYP. increases alpha MSH stimulates SNS to increase BMR decreases insulin.
What is adipostat?
The theory and mechanisms of controlling body fat
What does alpha MSH do?
Mostly Stops Hunger (derived from POMC). It is released in response to high leptin.
What are anorexigenic peptides?
in response to high leptin
inhibit feeding behaviour
eg alpha MSH
CART
what are orexigenic peptides?
in response to low leptin
activate feeding behaviour
eg NPY
AgRP
Genetic causes of obesity?
Melanocortin receptor (MC4R)
Leptin
Leptin receptor
POMC
What is the Melanocortin receptor?
aka MC4R
alpha MSH stimulates
AgRP blocks it
If genetic defect of it - no Mostly Stop Hunger signals.
