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Flashcards in regulation and integration of metabolism Deck (45):
1

direct signaling for nervous system control of organ function

autonomic nervous system

2

indirect signaling for nervous system control of organ function

neuroendocrine

3

hypothalamus direct control

autonomic: innervation of pre-ganglionic neurons
both sympathetic and parasympathetic

4

hypothalamus indirect control

hormonal: release of pituitary and adrenal cortex hormones

5

what are the three parts of the autonomic nervous system

sympathetic
parasympathetic
enteric nervous system

6

neurotransmitter of parasympathtic

both pre and post ganglionic use acetylcholine

7

neurotransmitter of sympathetic

pre uses acetylcholine
post use norepinephrine

8

autonomic control of cardiac function

carotid body detects O2/CO2 composition (chemoreceptors) CNIX
baroreceptors in heart detect blood pressure
CNX

9

the enteric nervous system characteristics

mesh of neurons in the gut
both parasympathetic and sympathetic
can function independently of the CNS

10

the neuroendocrine system the key players

hypothalamus
pituitary
adrenal glands
**diffuse, system wide endocrine signaling

11

anterior pituitary uses what type of system

portal system

12

the substances released from the hypothalamus are called what?

releasing factor

13

the substances released from the pituitary are called what?

tropins

14

under stress what hormone does the hypothalamus release?

corticotropin releasing hormone (CRH)

15

under stress what hormones does the ant. pit. release

adrenocorticotropic hormone (ACTH)

16

under stress what hormone is released from adrenal cortex?

cortisol

17

what nervous system is directly connected to the adrenal glands?

sympathetics

18

what is an example of an eicosanoid?

PGE2, from arachidonate acid

19

what is an example of a peptide hormone

insulin, glucagon

20

catecholamine examples

epinephrine, dopamine, serotonin

21

what things does the liver do

blood sugar
carbohydrate storage
amino acid content
lipid formation and mobilization
first pass metabolism

22

what things does the pancreas do

insulin release
glucagon
small intestine buffering
protease release

23

glucose-6-phosphate fate in liver

glycolysis to pyruvate to CAC
made into glucose and released into blood via glucose-6-phosphatase in ER
enter pentose phosphate pathway ->NADPH

24

when pyruvate is enters the matrix of mitochondria what can happen?

enter CAC
fatty acid synthesis

25

what is the cori cycle

under demanding activity
glycogen->lactate->blood lactate->enters liver->made into glucose->released into blood as blood glucose

26

why is NADPH important?

fatty acid synthesis
free radical degredation

27

how do AAs get into the liver

from the blood as glutamate or glutamine or alanine

28

once glutamine is in the liver what happens

enters the urea cycle which forms urea (two amine groups)

29

how does alanine get into the liver

pyruvate from muscle is converted into alanine by taking the amine group from glutamate
-travels in the blood to the liver
-once in the liver alanine donates the amine group to alpha ketogluterate and makes glutamate and pyruvate
-pyruvate is then converted to glucose and released into the blood
**glutamate is not used to transfer amine groups because it takes carbon backbones from the CAC

30

once AAs are in the liver what happens to them?

protein syn
fatty acid syn
glycolysis
CAC

31

fatty acid liver metabolism
how do they get there?

diet (chylomicrons)
adipose tissue(albumin)

32

once in the liver what happens to FAs

beta oxidation (makes NADH)
liver lipids
cholesterol formation (acetyl CoA) only in liver
ketone bodies (acetyl CoA) no glycerol

33

when adipose tissue reaches its capacity it releases what hormone?

leptin

34

what does leptin do?

goes to hypothalamus to eat less and metabolize more

35

what does ghrelin go?

tells you to eat more and metabolize less

36

what do insulin and satiety signals do?

tells you to eat less and metabolize more by turning off the ghrelin pathway

37

does leptin inhibit/activate fat synthesis and does it inhibit/activate beta oxidation?

inhibit
activate

38

when glucose is high it enters GLUT2 channels in cells and in particular beta cells and inhibits potassium from leaking out by inhibiting ATP-gated K channels. this leads to what?

-depolarization of the membrane and calcium voltage gated channel to open
-this causes the release of insulin granules
-as glucose decreases this stops due to less glucose and ATP in the beta cells

39

alpha cells are inhibited by what?

insulin, GABA and somatostatin

40

T/F glucagon is constitutively released at low glucose levels

true

41

fates of glucose in a well fed state

insulin release
glycogen formation
glycolysis which leads to triglycerides and taken to adipose tissue via VLDL

42

fates of glucose in fasting state

glucagon release
glycogenolysis ->glucose-6-phosphate
protein metabolism->AA->pyruvate->gluconeogen.
fatty acid metabolism->ketone bodies->brain

43

what are ketone bodies important for?

maintaining neurological function during a fasting state

44

starving state

-body breaks down muscle which releases AAs
increased production of urea
-fatty acid release->beta oxidation->acetyl-CoA->ketone bodies or glucose via gluconeogenesis

45

what are the ketone bodies that are formed?

acetone-toxic
beta-hydroxybutyrate -main source of energy
acetoacetate