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JazGI > Physiology > Flashcards

Physiology Flashcards

1
Q

3 main functions of saliva

+2 others

A 
lubrication
protection
digestion
(increases prior to emesis to neutralise
facilitates infants suckling)
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2
Q 
In saliva:
\_\_\_  buffer bacterial acids
\_\_\_\_ prevents enamel demineralisation
\_\_\_ coats teeth decreasing bacterial adherence
\_\_\_ attacks bac cell wall
\_\_\_ chelates Fe so bac can't grow
\_\_\_ for immunity
A 
HCO3 and PO4 and mucus buffer
high Ca2+ for enamel
protein coats teeth
lysozyme attacks wall
lactoferrin chelates Fe
IgA immunity
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3
Q

Enzymes in saliva and food they digest

A

α-amylase breaks α-1,4 bonds in carbs

lingual lipase for fats

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4
Q

In saliva NA+, Ca2+,Cl-,I-,PO4 2- are in higher/lower concn than in plasma

A

lower concn in slaiva

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5
Q

In saliva K+ and HCO3 - are in higher/lower concn than in plasma

A

higher concn in saliva

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6
Q 
As rate of saliva secretion increases:
\_\_\_ increases (provides optimum pH for \_\_\_) and \_\_\_ decreases
A

HCO3- increases ; α-amylase (neutral/alkali)

K+ decreases

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7
Q

4 organs that move with respiration

A

spleen
stomach
liver
gallbladder

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8
Q

Organs suspended in mesentery move ___ to line of mesentery fixation

A

perpendicular

in 1 plane

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9
Q

Primary secretion of saliva is from ____

it is __tonic and has a ___ composition to plasma

A

acinar cells

isotonic + similar in composition to plasma

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10
Q

In primary saliva secretion: Basolateral ____ drives K+ __ cell and Na+ __ cell =>

1) basolateral ____ to drive 2Cl-, 1Na+ and 1K+ __ cell
2) Cl- faciliated diffusion __ into ___ by ___

A

NaKATPase - K in and Na out

1) triple transporter - into cell
2) efflux into lumen by Ca2+ activated Cl- channels

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11
Q

In primary saliva secretion:
K+ into duct by ___
Na+ into duct through __causes __ to follow through +

A

apical Ca2+ activated K+ channels
Na+ through paracellular pores
H2O follows through paracellular pores + apical aquaporin 5

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12
Q

2ndry modification of saliva secretion is by ,+_
Overall effect =
by removing __, adding __ and duct cells being impermeable to __

A

striated, intercalated and excretory ducts
diluting effect (more ions are removed than are added)
Na+ Cl- removed
K+ and HCO3- added
impermeable to H2O

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13
Q

Channels involved in 2ndry modification of saliva

A 
driven by NaKATPase
K+ channel
ENaC
Na+H+exchanger
HCO3-/Cl- antiporter regulated by CFTR
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14
Q

Causes Na+ influx into apical cells in 2ndry modification of saliva:

A

ENaC (epithelial Na channel)

Na+H+ exchanger

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15
Q

Unconditioned reflex of saliva secretion =

A

chemo+mechano mouth receptors send afferents to NTS -> salivary nuclei in medulla -> parasymp. CNVII (submandibular and sublingual) CNIX (parotids)

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16
Q

Conditioned reflex of saliva secretion =

A

Thought/smell of food -> cerebral cortex -> salivary nuclei in medulla -> parasymp. CNVII (submandibular and sublingual) CNIX (parotids)

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17
Q

Parasympathetic supply to salivary glands causes:

1) increased synthesis and secretion of ___+__ = __
2) __ of myoepithelium mediated by __ receptors
3) __ blood flow mediated by __

A

α-amylase+ fluid = large volume, watery, enzyme rich secretion
contraction by M3/M1
increased by VIP

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18
Q 
Sympathetic supply (in stress) to salivary glands causes:
1) increased secretion of _,_+_ = _
2)\_\_ of myoepithelium
3) \_\_ blood flow
mediated by
A

α-amylase, K+ and HCO3- = small volume, mucous-rich secretion
contraction
decreased
α and β1 adrenoceptors

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19
Q

Sympathetic supply to salivary glands is via __

A

thoracic via superior cervical ganglia

adrealine

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20
Q

Symp/Para usually dominates supply to salivary glands?

A

Parasympathetics

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21
Q

__ and ___ cause xerostomia by blocking M1/3 receptors involved in parasympathetic release of saliva

A

M antagonists (eg. atropine) and antidepressants

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22
Q

CN__ causes stomach to relax and expand

A

CNX

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23
Q

Muscle thickness ___ as go from fundus to antrum

A

increases

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24
Q

retropulsion =

A

peristalsis of stomach against closed pyloric sphincter churns food

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25
Q

Increased volume and consistency of chyme in the stomach cause the stomach to ____ causing: (4)

A

distend =>

Increased SM motility of stomach, activity of intrinsic nerve plexi, gastrin release and CNX activity

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26
Q

enterogastrones eg. ___ (2) are ____ that delay the release of chyme into the duodenum

A

CCK and secretin

hormones

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27
Q

enterogastric reflex ___ stomach emptying into duodenum via __+__

A

delays

intrinsic nerve plexi and autonomic NS

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28
Q

Factors in the duodenum that delay gastric emptying (4)

A

distension
fat
acidity
hypertonicity

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29
Q

Dumping syndrome is when:

A

osmotically active products of carb and protein breakdown attract water into duodenum from plasma and cause a decrease in plasma vol. and circulatory disturbance

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30
Q

Pyloric gland area in the stomach has ++_ cells

A

mucus secreting
D (somatostatin)
G (gastrin) cells

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31
Q

Oxyntic mucosa is found in + of stomach

Contains +++

A 
fundus and body
mucus secreting
Chief (pepsinogen)
ECL (histamine)
parietal (HCl, intrinsic factor)
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32
Q

B12 is absorbed in the ___

A

terminal ileum

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33
Q

H+ is driven into parietal cell canaliculus by ____ on ___ in exchange for __

A

H+K+ATPase on apical membrane

K+

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34
Q

Inhibitors of HCl secretion in the stomach = +

A

PGE2

D cells -> somatostatin => decreased gastrin between meals

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35
Q

Stimulators of HCl secretion

A

Parasympathetic postganglionic nerves -> M1 on ECL and M3 on parietal
Gastrin-> parietal+ECL

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36
Q

Catalyses CO2+H20 -> H2CO3 in parietal cells
H2CO3 goes on to produce H+
and HCO3 which is basolaterally pumped out in exchange for Cl

A

carbonic anhydrase

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37
Q

3 stages of gastric secretion

A

cephalic
gastric
intestinal

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38
Q

What happens in cephalic stage of gastric secretion?

A

occurs before food reaches stomach
CNX -> increases ACh, histamine, gastrin, decreases somatostatin =>
INCREASES PARIETAL SECRETION

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39
Q

What happens in gastric stage of gastric secretion?

A

mechanoreceptors (distension) -> increase ACh secretion (for M3) and gastrin
protein digestion products increase gastrin =>
INCREASED PARIETAL SECRETION

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40
Q

What happens in intestinal phase of gastric secretion?

A

small intestine factors decrease acid production and low pH in stomach = somatostatin release =>
DECREASED PARIETAL SECRETION

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41
Q

Factors that protect gastric mucosa from HCl and pepsin

A

mucus gel layer with hydrophobic monolayer on top
PGE2 and PGI2 decrease acid secretion
mucus and HCO3- secretion
mucosal blood flow moves H+ to blood

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42
Q

H. pylori is found in ___ in stomach and causes ____ which weakens the mucus barrier

A

mucus gel layer

persistent inflammation

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43
Q

assimilation =

A

digestion+absorption

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44
Q

absorption in the GI tract =

A

molecules crossapical and basolateral membrane of enterocytes into interstitium

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45
Q

glucose α-1,2-fructose =

A

sucrose

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46
Q

glucose β-1,4- galactose =

A

lactose

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47
Q

oligosaccharide eg.s =

A

sucrose and lactose

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48
Q

brush border enzymes for oligosaccharide>monosaccharide digestion =

A

lactase, maltase, sucrase-isomaltase

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49
Q

intraluminal digestion of polysaccharides to oligosaccharides is by:

A

hydrolyisis by α-amylase

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50
Q

α-amylase is a ___enzyme meaning it only breaks ___ bonds and NOT //_ bonds

A

endoenzyme breaks internal α-1,4 bonds

NOT α-1,6/terminal/next to branch point bonds

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51
Q

lactase is/isnt the rate limiting step in lactose assimilation

A

IS

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52
Q

Breaks α-1,4 bonds in oligosaccharides of

A

maltase

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53
Q

only enzyme to break α-1,6 bonds in oligosaccharides

A

isomaltase

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54
Q

absorption of the breakdown products of carb.s occurs in the ___+___

A

duodenum and jejunum

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55
Q

glucose and galactose are absorbed across the apical membrane in the gut by ___ by ___ with ___

A

2ndry active transport by SGLT1 with 2Na+

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56
Q

fructose is absorbed across the apical membrane in the gut by ___

A

GLUT5

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57
Q

monosaccharides are absorbed across the basolateral membrane in the gut by __ by ___

A

facilitated diffusion by GLUT2

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58
Q

pepsin is a __peptidase
optimum pH =
Preference for + AAs
Not essential enzyme

A

endopeptidase
1.8-3.5
aromatic+larger neutral AAs

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59
Q

Protein digestion / can be transported across apical and basolateral membrane of enterocytes

A

peptides

AAs

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60
Q

Locations where peptides can be broken down to AAs (3)

A

apical brush border enzymes
intracellular hydrolysis
luminal enzymes

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61
Q

5 pancreatic enzymes that breakdown protein in ___

endo + exopeptidases

A

duodenum
endo = trypsin, chemotrypsin, elastase
exo = carboxypeptidase A+B (cleave at COOH end)

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62
Q

pancreatic enzymes convert protein in duodenum to __% oligopeptides and __% AAs

A

70% oligopeptides

30% AAs

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63
Q

Brush border peptidases have affinity for __peptides of length
exo+/endo?

A

longer 3-8AAs

endo and exopeptidases (carboxy+aminopeptidases - cleave at NH3 end)

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64
Q

cytoplasmic peptidases hydrolyse ____

A

di/tri peptides

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65
Q

AA absorption at brush border is by:
1) 5 different ____
It is a form of ___ using E from __ on basolateral membrane
2) 2 ___ mechanisms

A

1) 5 Na+ co-transporters
2ndry active transport
Na+K+ATPase
2) 2 Na+ independent

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66
Q

Hartnup disease caused by:

A

dysfunction of 5 Na+ co-transporter mechanism for AA absorption at brush border for neutral AAs

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67
Q

Cystinuria caused by:

A

dysfunction of 2 Na+ independant mechanisms of AA absorption at brush border membrane for cationic AAs

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68
Q

5 mechanisms of AA transport at the basolateral membrane =

A 
3 = efflux Na+ independent
2 = influx of Na+ dependent (AAs needed for cells nutrition)
69
Q

Gastric phase of lipid digestion

A

mix with gastric lipase and slowly broken down

free FAs stimulate CCK and pancreatic lipase release

70
Q

Secretion of bile is stimulated by __

A

CCK

71
Q

__ secreted from ___ is needed to allow lipase access to FAs covered in bile salts

A

colipase

pancreas

72
Q

digestion of lipids in the duodenum products =

A

2 FAs

2-monoglyceride

73
Q

Absorption of FAs and monoglycerides occurs by __ in the gut

A

passive diffusion

74
Q

Short and medium (less than 12C) FAs diffuse into __ when absorbed in gut
long and monos are made into _ and transported in __ to __

A 
short+medium = villus capillaries
long+monos= tris > chylomicrons > lacteal
75
Q

Cholesterol is absorbed from gut by ___into ___ by ___

carried by ___ to ___ where it is released and __ returned to ___

A

endocytosis into clatherin coated pits by NPC1L1
myosin > endocytic recylcing compartment
NPC1L1 to membrane

76
Q

Drug that blocks NPC1L1 involved in cholesterol absorption

A

ezetimibe

77
Q

Vomiting is controlled by ___ in ___ of brain

A 
vomiting centre (VC)
medulla oblongata
78
Q

Frequently precede vomiting

A

increased salivation
sweating
nausea
Increased HR

79
Q

Vomiting:
First ___ is suspended
_____ ileum to stomach
stop ___ and close __ to prevent aspiration
__relaxes, + contract to compress relaxed stomach

A

intestinal slow wave activity
retrograde contractions
breathing ; glottis
LOS relaxes ; diaphragm + abdominal muscles contract

80
Q

Nausea causes relaxation of + => __ in their muscles =>afferents > contraction of __+__ = contents of jej.,duo and pylorus go to +

A

stomach and LOS
tension
upper small intestine and pyloric sphincter
body and fundus

81
Q

Things that stimulate vomiting (5)

A

toxins in gut/blood
mechanical
motion sickness
psychological/pain

82
Q

In the stimulation of vomiting:

__+__ go to the CTZ in the area postrema of the brainstem

A

absorbed toxins in the blood (there is no BBB in CTZ)

vestibular system>vestibular nuclei (eg. motion sickness)

83
Q

In stimulation of vomiting:

stimuli from CNS eg. psychological go to ___ and __ then to ___

A

cerebral cortex+limbic system

medulla

84
Q

Toxins in the gut lumen/systemically stimulate ___cells to release __ to activate __ receptor and send a depolarising sensory afferent to the mucosa where become ___ to the ___

A 
enterochrommafin
5-HT
5-HT3
vagal afferents
brainstem (CTZ and NTS)
85
Q

In stimulation of vomiting:

__+__ cause signals to be sent to brainstem (CTZ and NTS)

A

mechanical stimuli/pathology in GI tract or other viseral organs
toxins in gut lumen or systemically

86
Q

VC coordinates vomiting , its output is via +

A

vagus nerve

spinal motor neurones

87
Q

VC = a group of _____ in ___ driven by ___ which receives input from ___

A

interconnecteed neurones
medulla
central pattern generator
NTS

88
Q

Vagal output from VC causes… (3)

A

longitudinal muscle in oeso to contract and shorten
proximal stomach relaxes
small intestine = retrograde contraction

89
Q

somatic motor neurones from VC cause … (2)

A

anterior abdominal and diaphragm contract

90
Q

autonomic/ somatic efferents from VC cause … (4)

A

Heart rate and force increase
increase salivary secretions
pale and clammy skin
anal and bladder sphincters contract

91
Q

Consequences of vomiting =

A

dehydration
hypokalaemia (due to HKATPase)
loss of H+ and Cl- => hypochoraemic metabolic alkalosis
Mallory-Weiss tear
Rarely - loss of duodenal HCO3- =metabolic acidosis

92
Q

Chemo and radiotherapy cause vomiting due to __

A

5-HT and substance P from enterochrommafin cells

93
Q

___ for parkinsons stimulates vomiting by agonising __

A

levodopa

D2 receptors in CTZ

94
Q

Plicae circulares in small intestine synonym =

A

folds/valves of Kerckring

95
Q 
2 eg.s of incretins and where they are secreted from
function =
A

GIP - K cells in duod and jej
GLP-1 - L cells in small int
stimulate β cells in panc to produce insulin

96
Q 
Secretin is secreted from \_\_\_
function =
A

S cells in duodenum
stimulates release of pancreatic, bile release and CCK
chief cells -> pepsinogen

97
Q 
Motilin is secreted from \_\_\_
function =
A

M cells in duodenum and jejunum

stimulates muscle contractions to clear food to colon

98
Q 
CCK is secreted from \_\_\_
function =
A

I cells in duo + jejunum
decreases gastric emptying, HCl
Increases pancreatic and bile release

99
Q 
Gastrin is released from \_\_\_
function =
A

G cells of antrum (mainly) and duodenum
HCl release
antrum contractions
decreased rate of gastric emptying, pancreatic + gallbladder secretions

100
Q

Ghrelin is released from ___

A

Gr cells in antrum, small intestine and elsewhere eg. pancreas

101
Q

All peptide hormones secreted from the small intestine act on ___ receptors

A

G-protein coupled

102
Q

succus entericus from the small intestine contains:

A 
mucus (goblet cells)
aqueous salts (crypts of Lieberkuhn, no enzymes
103
Q

Succus entericus:
Cl- out via ___ and + follow
excessively activated in __
control mechanisms =

A 
CFTR
H2O and Na+
diarrhoea - cholera
distension/irritation, gastrin, CCK and para (increases)
sympathetic (decreases)
104
Q

___ in ___ ileum stimulates gastroileal reflex

A

gastrin

empty ileum

105
Q

due to segmentation food takes ___ to move through small intestine

A

3-5 hrs

106
Q

strength of segmentation in small intestine increases with ___ and decreases with __ stimulation

A 
increase = para
decrease = symp
107
Q

In fasting state peristalsis =
1)
2)

A

1) few localised contractions

2) MMC - every 90-120mins - clears debris

108
Q

MMC controlling factors =

A

decreased by: feeding, vagal, gastrin, CCK

increased by motilin (macrolides mimic)

109
Q

Enzymes in zymogen granules in pancreatic acinar cells =

A

pancreatic amylase and lipase

110
Q

Pancreatic acinar cells secrete:

A

pancreatic amylase and lipase
trypsinogen
chymotrypsinogen and procarboxypeptidase A+B

111
Q

chymotrypsinogen + Procarboxypeptidase A+B are activated by ___
trypsinogen is activated by ___

A

chymo + procarb - trypsin

trypsinogen - duodenal enterokinase from mucosal cells

112
Q

Duct cells in pancreas secrete ___ rich fluid (+ follow through pores)
___ pumps out Cl- used to drive ____

A

HCO3-
Na+ and H2O
CFTR drives Cl-/HCO3- antiporter

113
Q

cephalic phase of pancreas exocrine control

A

vagal nerve stimulates acinar cells (20% of secretion)

114
Q

gastric phase of pancreas exocrine control

A

distension>vasovagal reflex> para stim.s acinar and duct cells (5-10%)

115
Q

intestinal phase of pancreas exocrine control

A

acid> secretin> duct cells> increased aqueous NaHCO3-
fat+protein > CCK>acinar>more enzymes
(70-75%)

116
Q

Length and diameter of colon =

A

1.5m

6cm

117
Q

ileocaecal valve is controlled by:

A

vagal, symp and enteric neurones

118
Q

Functions of the large intestine

A

absorb: H2O, Na+, Cl-, short chain FAs (bac fermentation of undigested carb
secrete: K+, HCO3- and mucus
storage
excretion

119
Q

Mass movements in the colon (2)

A

1) asc and transverse - caused by gastrocolic response - gastrin+extrinsic nerves in response to food: 1-3x daily
2) distal colon - may trigger defaecation reflex

120
Q

rectosphincteric reflex =

A

distension of rectum > active contraction of rectal SM > internal anal sphincter relaxes

121
Q

Functions of colonic flora

A 
immunity
motility promotors
mucosal integrity
obstruction
synthesis vitamin K2 and FAs
activate some drugs
122
Q

Hirschprung’s disease =

A

congenital megacolon

colon lacks part of enteric NS and causes obstruction/severe constipation

123
Q

composition of faeces =

A

100ml H2O

50ml cellulose, bilirubin and bacteria

124
Q

Diarrhoea = loss of fluid and solutes from GI tract in excess of ___

A

500ml per day

125
Q

Absorption of H2O in gut is ___ and driven by ___

A

passive

transport of solutes

126
Q

Gut secretes ___l per day of fluids
small intestine absorbs __l
colon absorbs ___

A

9.3l
8.3l
90% of the litre left

127
Q

Main cause of postprandial Na+ absorption =

location =

A

Na+/glucose and Na+/AA cotransporters

in small intestine (mostly jejunum)

128
Q

Na+/glucose and Na+/AA cotransporters are a form of ___ as function with Na+K+ATPase on the basolateral membrane.
They are ___ and so make the lumen ___ and drive __ into interstitium
not regulated by

A 
2ndry AT
electrogenic
-ve
Cl-
NOT regulated by cAMP or Ca2+
129
Q

Na+/H+ exchange (without a parallel Cl-/HCO3- exchanger) occurs in the ___ and is stimulated by ___

A

duodenum and jejunum

HCO3- in the lumen

130
Q

Parallel Na/H+ and Cl-/HCO3- exchange occurs in the ___ and is most involved in H2O absorption in ____

A

ileum and proximal colon

interdigestive period

131
Q

Parallel Na/H+ and Cl-/HCO3- exchange is regulated by:

is electroneutral/genic

A

increased cAMP, cGMP, Ca2+ decrease NaCl absorption

132
Q

E. coli enterotoxin activates ___ to produce ___ which inhibits Parallel Na/H+ and Cl-/HCO3- exchange and so decreases NaCl absorption and causes ___

A

adenylate cyclase
intracellular cAMP
diarrhoea

133
Q

Na transporter in distal colon =

is stimulated by ____ which (3)

A 
ENaC
aldosterone (NOT cAMP or cGMP)
opens ENaC
increases no. of ENaC on membrane from intracellular pool
increases ENaC + NaKATPase synth
134
Q

Na transporters involved in water balance in the GI tract =

A

Na+/glucose Na+/AA co-transporters
Na+/H+ exchanger (w/wo parallel Cl-/HCO3- exchanger)
ENaC

135
Q

Passive Cl- absorption in the gut is driven by ___ due to
___ small intestine
___ colon

A

-ve potential
Na+/glucose+AA transporter = small intestine
ENaC = colon

136
Q

In the gut Cl- secretion is greater/less than absorption

It is secreted from __ cells

A

less than

crypt cells

137
Q

Basolateral transporters involved in Cl- secretion

A

NaKATPase (causes low Na intracellularly) drives
NKCC1 to pump inwards (increases Cl- intra concn)
IK1+BK (recycle/efflux K+ )

138
Q

Apical transporter for Cl- secretion in gut

Is indirectly activate by ___

A

CFTR
enterotoxins eg. choler, E. coli, C. diff
hormones and neurotransmitters eg. VIP, bradykinin 5-HT
immune cell products eg. PG and histamine
laxatives

139
Q

Secondary messengers that activators of CFTR stimulate to activate CFTR

A

cAMP (cholera toxin, VIP and histamine)
cGMP (E. coli toxin and guanylin)
Ca2+ (ACh, bradykinin, 5-HT)

140
Q

Main electrolyte driver of H2O absorption in the gut =

A

Na+

141
Q

Diarrhoea causes (3) due to loss of fluid and electrolytes

A

dehydration (na+ and H2O)
metabolic acidosis (HCO3-)
hypokalaemia (K+)

142
Q

Mechanisms behind causes of diarrhoea (4)

A

hypermotility
non/poor absorption of solutes in intestinal lumen
impaired absorption of NaCl
Excess secretion

143
Q

Treatment of diarrhoea =

A

fluids and elctrolytes
may need anti-infective agents
may need anti-motility eg. opiates or loperamide

144
Q

Diarrhoea caused by impaired absorption of NaCl eg.s

A

congenital chloridorrhea = no exchanger
inflammation
infection (E. coli, campylobacter toxins)
excess bile acid in colon

145
Q

Vitamin D is activated by __

A

liver

146
Q

hepatocytes are arranged between sinusoids in plates _ cells thick

A

2

147
Q

Basolateral membrane of hepatocytes faces the ___

which lies between it and the endothelial cells of sinusoid

A

pericellular space (of Disse)

148
Q

apical membrane of hepatocyte is __+ forms

A

groove

forms canaliculi

149
Q

stellate/__ cells store __ and are found in the ___

A

Ito
vitamin A
space of Disse

150
Q

Intrahepatic biliary system = canaliculi> terminal bile ductules >___ ducts > ___ ducts>___ducts>__ ducts>R+L hepatic ducts

A

perilobular
interlobular
septal
lobar

151
Q

_-__l of bile is produced each day

A

0.6-1.2l

152
Q

__+__ are stimulated by chyme in duodenum to cause gallbladder SM to contract
___ opens the sphincter of Oddi

A

CCK and CNX

CCK

153
Q

75% of bile comes from secretions from __

25% from __

A 
75% = hepatocytes
25% = bile duct cells
154
Q

bile duct cell secretion is similar to __secretion and properties =

A

pancreatic
alkaline
aqueous Na+ K+ Cl- HCO3- rich

155
Q

Between meals bile duct cell secretion is similar to __ in ionic composition
during meals flow rate ____ due to secretin and __ transporter activity ___ so HCO3- content ___

A 
plasma
increases
HCO3-/Cl-
increases
increases HCO3- content during meals
156
Q

Bile secretions that are produced in hepatocyes =

A

primary bile acids - mainly cholic and chenodeoxycholic acids, H2O and electrolytes, lipids, phosholipids, cholesterol, IgA and bilirubin

157
Q

bilirubin is from ___ of RBCs

A

porphyrin

158
Q

primary bile acids + __ = bile salts

many are conjugated to __/__

A

Na+ or K+

glycine/taurine

159
Q

__% of bile salts are recycled. The reabsorption occurs in the __

A

95%

terminal ileum

160
Q

Ileum bile salt transporter = __
on liver transporter for influx = ___
on liver transporter for efflux to gallbladder/duod =__

A

ASBT (Na+ coupled)
NTCP (Na+ coupled)
MRCP2+ABCG2 pumps

161
Q

Secretin stimulates a ____ bile secretion

A

aqueous alkaline

162
Q

Relief of biliary colic =

A

atropine/GTN

163
Q

Analgesics for biliary colic = __

A

morphine (but constricts sphincter of Oddi)
buprenorphine
pethidine

164
Q

more/less polar drugs are excreted by the kidney

A

more polar

165
Q

Liver metabolises __ to active form

and __ to increased activity form ___

A

ACEIs

codeine-> morphine

166
Q

Phase 1 in liver metabolism of drugs =

A

make drug more polar + make handle for conjugation = functionalisation

167
Q

In phase 1 drug metabolism oxidation is mediated by ___ and is for ___ drugs

A

CYP family of monooxygenases

lipid soluble

168
Q

Phase 2 of drug metabolism in the liver = ___ with __

it increases the ___ and so usually leads to __ products

A

conjugation with glucaronyl/sulphate/methyl/acetyl
increases polarity
inactive products

JazGI (26 decks)

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