appetite

Question 1

how many regulatory peptide hormones released by GIT

Answer 1

> 20

Question 2

3 functions of gut hormones

Answer 2

influence processes including gut motility, secretion of other hormones and appetite

Question 3

what is gut hormone release regulated by

Answer 3

gut nutrient content

Question 4

GIT hormones and location

Answer 4

slide 35

Question 5

what do enteroendocrine cells have, and what do these allow them to do

Answer 5

receptors on apical membrane; contain molecular machinery to respond to different food types (e.g. type of macromolecule, length etc.); release hormones from basal membrane for paracrine or endocrine effects, or to modulate neuronal function

Question 6

what hormone is released from stomach, and 2 basic functions

Answer 6

ghrelin, involved in hunger and growth hormone release

Question 7

ghrelin length and what attaches fatty acid chain to it

Answer 7

28 amino acids long; has faty acid chain attached by ghrelin O-acyltransferase

Question 8

when does ghrelin have effect

Answer 8

decreases when food intaken, but steadily rises until eat again

Question 9

how does ghrelin increase appetite, and effect on food intake

Answer 9

directly stimulates NPY/Agrp and inhibits POMC neurons, increasing food intake

Question 10

2 gut hormones released by colon, and enteroendocrine cell they’re released from

Answer 10

GLP-1, PYY3-36 from L cells (apical membrane in contact with lumen of gut, with secretory granules near broad basal membrane; can also synapse with neurones)

Question 11

what is GLP-1 involved in

Answer 11

incretin activity, satiation

Question 12

what is PYY3-36 involved in

Answer 12

satiation

Question 13

describe post-prandial secretion of PYY

Answer 13

goes up rapidly after heavy meals

Question 14

how does PYY decrease appetite, and effect on food intake

Answer 14

directly inhibits NPY release and stimulates POMC neurons, reducing food intake

Question 15

what gene codes for glucagon-like peptide-1 (GLP-1) and when is it released

Answer 15

coded for by preproglucagon gene, and released post-prandially

Question 16

processing of pro-glucagon in intestinal L-cells

Answer 16

prohormone convertase 1 removes GLP-1 (active agonist) from pro-glucagon; quickly turned off by DP-IV which shortens half life (regulated by inactivation)

Question 17

incretin roles of GLP-1

Answer 17

stimulates glucose-stimulated insulin release (possible treatment for type 2 diabetes), reduces food intake

Question 18

GLP-1 as treatment of type 2 diabetes: modification

Answer 18

molecules bind to it to increase half-life, or to inhibit DP-IV so endogenous breakdown reduced

Question 19

what is saxenda

Answer 19

long-acting GLP-1 receptor agonist (liraglutide) at double dose used for type 2 diabetes, causing weight loss

Question 20

GIT hormones at treatment of obesity

Answer 20

all from L-cells so attempt to suppress appetite and food intake by targeting these

Question 21

3 types of satiety action of gut hormones

Answer 21

post-prandial, chronic, acute nausea

Question 22

purpose of post-prandial satiety action of gut hormones

Answer 22

reduces food intake following meal

Question 23

chronic satiety action of gut hormones

Answer 23

gut disease, with chronic elevation suppressing appetite

Question 24

acute nausea satiety action of gut hormones

Answer 24

toxin ingestions - acutely very high levels

Question 25

gut hormones as drug targets to treat obesity byh reducing appetite

Answer 25

high dose will cause nausea, then drops quickly downt o no effect (only small peiod it is in useful effects of anorexigenic and increase glucose tolerance)

Question 26

2 mechanisms of dietary manipulation

Answer 26

synthetic nutrients to stimulate nutrient receptors, deliver nutrients to specific regions of gut