Wk3 H20, Electrolyte, Intestinal Motility Flashcards Preview

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Flashcards in Wk3 H20, Electrolyte, Intestinal Motility Deck (24):
1

substance that promotes bowel loosening and movement

Purgative

2

feeling of needing to pass stool even when bowel is empty

tenesmus

3

Location of cells that absorb fluid:

tips of villi

4

Location of cells that secrete fluid:

crypts

5

How does sodium get in apical side for water to follow?

NHE

(sodium hydrogen exchanger)

6

How does chloride get in apical side to join sodium and water follow?

Chloride/Bicarb exchanger

7

Electrogenic uptake of water?

Na+ / Glucose (SGLT1-apical) (GLUT-2, basolateral)

**Cl- and H20 follow passively via tight junctions

8

long reflex regulator of Cl- secretion:

Ach

VIP

9

GI peptide in goblet and ECL cells

increases cGMP

promotes Cl- secretion via CFTR

Guanylin

10

Drug that activate guanylate cyclase type C to treat constipation:

Linaclotide

11

The bulk of fluid reabsorption is driven by?

Nutrient-coupled electrogenic sodium absorption

SGLT-1
Na/AA

12

How does sodium enter COLONOcytes?

ENaCs

electrogenic

mostly in distal colon

13

What stimulates ENaC expression in colonocytes?

Aldosterone

just like the kidney!

14

How does electroneutral NaCl absorption occur n the colon?

NHE's

Na+/H+

15

Name some secretagogues (enhance secretion)

PNS--Ach

VIP/NO

Histamine

PG's

gastrin

secretin

motilin

serotonin

LCFAs

bile salts

Bacterial toxins

16

Name some absorbagogues (enhance absorption):

SNS

somatostatin

Aldosterone

SCFAs

opiods

17

Diarrhea from excess secretion of CL-?

Secretory

18

Diarrhea from poor absorption of nutrients?

Osmotic

19

What regulates intestinal motility?

BER (basal electric rhythm) --- cells of Cajal?

Enteric nervous system

20

BER cycle rate in jejunum vs ilium?

jejunum -- 12/min

distal ilium -- 8/min

21

See slide 31 and 35

for specific regulators of motility

22

BER at ileocecal valve vs sigmoid colon:

IC valve -- 2/min

SC -- 6/min

23

Excess production of what causes Inlammatory Bowel Disease sx?

NO

**caused by Crohn's or ulcerative colitis

24

Intestine becomes more sensitive and contract more frequently?

Irritable Bowel Syndrome