(44) Intestinal Secretion

Question 1

(Understand the organizational structure of the gut)

do it

villi increase surface area

lacteals - involved in lipid transport

base of villi - crypt epithelium - stem cells - give rise to other cells - crypt specific problems are really bad

Answer 1

do it

Question 2

(Cell types and Structures in the Intestine)

(Say what each of these does)

1. villus epithelial cells
2. brush border
3. crypt epithelial cells
4. enteroendocrine cels
5. goblet cells
6. lacteals
7. brunner’s glands
8. paneth cells
9. stem cells
10. peyer’s patches
11. plexus neurons

Answer 2

1. absorptive
2. digestion/absorption
3. secretion (water, HCO3)
4. hormones (2o types)
5. mucus
6. chylomicrons
7. mucus
8. lysosomal hyrdolases
9. progenitor cells
10. lymphoid follicles
11. smooth muscle regulation

Question 3

(Differentiate duodenal, jejunal, and ileal structure)

just look at these slide - they are on the ipad

there are three of them

Question 4

(Understand net water turnover in the GI tract)

learn this

don’t memorize numbers - know the general numbers

Question 5

(Understand Biology of the Crypt Epithelium)

1-3. Stem cells in crypt give rise to what other 3 cell types (what is the function of each type)?

Answer 5

1. crypt cells –> secretion
2. goblet cells –> mucus
3. enterocytes –> absorption

Question 6

(think of this as a crypt cells)

1. does sympathetic (NE) inhibit or stimulate secretion of water and chloride?
2. does parasympathetic (Ach - cholinergic) inhibit or stimulate secretion of water and Cl-?
3. opiod neurons also dive down into circular smooth muscle (also effect smooth muscle - causes segmentation) + inhibit secretion - they also innervate epithelial cells and increase Na+, Cl-, and water absorption
4. inflammation, infection are responsbile for PMN and Mast cell (5-HT is aka serotonin) - so they basically cause diarrhea

Answer 6

1. inhibits
2. stimulate

Question 7

(Cryptosporidium parvum infection)

1. Causes expression of what two substances?
2. PGI2 acts on what?
3. overall effect is to do what?
4. PGE2 is direct, PGI2 is indirect

Answer 7

1. PGE2, PGI2
2. myenteric ganglion
3. increase Cl- and water secretion

(plus make note of IL-1b and TNFa which stimulate fibroblast)

(know that prostaglandin synthetase interferes - therefore a treatment)

Question 8

(Vibrio Cholera Toxin)

1. remember that 5HT is same as serotonin

just learn the diagram

on ipad

Question 9

(Pathogenesis of E. Coli Diarrhea)

1. produce STa (toxins) that stimulate what?

get a general idea of figure - he wasnt do adamant about this

Answer 9

1. guanylate cyclase (GC)

Question 10

(Anti-secretory therapy - non-specific therapies)

1. What drugs work as Prostaglandin Synthetase Inhibitors? (there are three)
2. what is the effet of these?

Answer 10

1. sulfasalazine, olsalazine, prednisone (not so good - lots of side effects)
2. reduce secretion

Question 11

(Anti-secretory therapy - non-specific therapies)

(u,delta-opiod agonists)

1-2. what are two drugs?

3. avoid in what?

Answer 11

1. loperamide
2. diphenoxylate (number of side effects - don’t use it)
3. collie dogs - limited ability to metabolize this drug

Question 12

(Anti-secretory therapy - non-specific therapies)

(5-HT3 Serotonin Antagonists)

1-4. What are the four drugs?

Answer 12

1. ondansetron
2. granisetron
3. tropisetron
4. dolasetron

(probably don’t worry much about memorizing these)

Question 13

(Anti-secretory therapy - non-specific therapies)

(a2-adrenergic agonsists)

1. What is the one drug?

Answer 13

1. clonidine

Question 14

(Anti-secretory therapy - non-specific therapies)

1-4. what are the four general therapies?

Answer 14

1. prostaglandin synthetase inhibitors
2. opiod agonists
3. 5-HT3 serotonergic antagonists
4. a2-adrenergic agonists

Question 15

(LOOK AT THIS)

inflammatory bowel disease

Answer 15

he didn’t really talk about this but here it is