Phys GI motility Flashcards Preview

GI & Liver Fall 2013 CBD > Phys GI motility > Flashcards

Flashcards in Phys GI motility Deck (28):
1

Connections between smooth muscle cells

nexus. means propagation without nerves

2

nature of chewing

stretch reflex

3

UES vs LES

UES is an anatomical sphincter
LES is not

4

Pressures in esophagus during swallowing
(5 items)

above 0 at UES, dropping, then rising in swallow
above 0 high up, including neck
below 0 in thorax, positive during swallowing
above 0 at & below diaphragm
above 0 at LES, lowers upon swallowing for entry

5

primary peristaltic wave

swallowing

6

secondary peristaltic wave

sth stuck in throate

7

distribution of muscle fiber types in esophagus

upper 1/3 striated
middle 1/3 transition (both)
lower 1/3 smooth (unaffected by vagotomy)

8

myogenic tone of sphincters

closed. NO from stimulus relaxes

9

location of oxyntic glands

stomach body

10

location of antrum

bottom by pylorus

11

pressure of stomach during swallow

drops to allow entry of food

12

gastric motility

wave goes down to pylorus increasing intensity, maintaining frequency

13

movement of food in stomach

most is squished back up (retropulsion)
very little pushed through pylorus

14

Need spikes for stomach contraction wave?

no, determined by height of plateau. spikes increase intensity

15

frequency of stomach contraction

3-5/min

16

3 things that reduce gastric emptying?

fat
acid
hyper/hypotonic solution

17

fastest emptying thing from stomach

isotonic water

18

SI motor pattern

irregularly spaced waves for stegmental mixing. no propagation

19

actions of SI

mixing
digestion
absorption

20

migrating motor complex

every 90 min in unfed SI ("housekeeper reflex")

initiated by motolin (from neurons)

21

effect of motolin

migrating motor complex

22

source of electrical stimulus in gut

interstitial cells of Cajal

23

trigger of contraction in stomach and SI

Stomach: waves
SI: needs action potential - spiking on top of slow wave. frequency can approach slow waves, but not exceed it. not propagated.

24

colon features

haustra (bubbles)
teniae coli (longitudinal muscle bands)

25

Ileocecal sphincter actions

control center

relaxation upon ileal distension
contraction on colonic distention
tonic resting contraction

controlled in the wall of the gut

26

mass movement

haustrations disappear in colon, sht moves, several times a day.

27

achalasia

failure to relax esophageal sphincter

28

megacolon

failure to relax rectal sphincter (absence of ganglion?)