Wk3 H20, Electrolyte, Intestinal Motility Flashcards Preview

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

substance that promotes bowel loosening and movement

A

Purgative

2
Q

feeling of needing to pass stool even when bowel is empty

A

tenesmus

3
Q

Location of cells that absorb fluid:

A

tips of villi

4
Q

Location of cells that secrete fluid:

A

crypts

5
Q

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

A

NHE

sodium hydrogen exchanger

6
Q

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

A

Chloride/Bicarb exchanger

7
Q

Electrogenic uptake of water?

A

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

**Cl- and H20 follow passively via tight junctions

8
Q

long reflex regulator of Cl- secretion:

A

Ach

VIP

9
Q

GI peptide in goblet and ECL cells

increases cGMP

promotes Cl- secretion via CFTR

A

Guanylin

10
Q

Drug that activate guanylate cyclase type C to treat constipation:

A

Linaclotide

11
Q

The bulk of fluid reabsorption is driven by?

A

Nutrient-coupled electrogenic sodium absorption

SGLT-1
Na/AA

12
Q

How does sodium enter COLONOcytes?

A

ENaCs

electrogenic

mostly in distal colon

13
Q

What stimulates ENaC expression in colonocytes?

A

Aldosterone

just like the kidney!

14
Q

How does electroneutral NaCl absorption occur n the colon?

A

NHE’s

Na+/H+

15
Q

Name some secretagogues (enhance secretion)

A

PNS–Ach

VIP/NO

Histamine

PG’s

gastrin

secretin

motilin

serotonin

LCFAs

bile salts

Bacterial toxins

16
Q

Name some absorbagogues (enhance absorption):

A

SNS

somatostatin

Aldosterone

SCFAs

opiods

17
Q

Diarrhea from excess secretion of CL-?

A

Secretory

18
Q

Diarrhea from poor absorption of nutrients?

A

Osmotic

19
Q

What regulates intestinal motility?

A

BER (basal electric rhythm) — cells of Cajal?

Enteric nervous system

20
Q

BER cycle rate in jejunum vs ilium?

A

jejunum – 12/min

distal ilium – 8/min

21
Q

See slide 31 and 35

A

for specific regulators of motility

22
Q

BER at ileocecal valve vs sigmoid colon:

A

IC valve – 2/min

SC – 6/min

23
Q

Excess production of what causes Inlammatory Bowel Disease sx?

A

NO

**caused by Crohn’s or ulcerative colitis

24
Q

Intestine becomes more sensitive and contract more frequently?

A

Irritable Bowel Syndrome