Shared Flashcard Set

Details

Ab Physio
Ab Physio
138
Physiology
Professional
02/02/2010

Additional Physiology Flashcards

 


 

Cards

Term
Bile comes from
Definition
liver hepatocytes and biliary duct cholangiocytes
Term
Hepatic bile high in
Definition
Cl, HCO3, pH
Term
Gallbladder bile high in
Definition
Na, K, Ca (positive ions), bile acids, lecithin, bilde pigments, cholesterol
Term
Bile also contains:
Definition

ATP and glutathione

Proteins such as biliary glycoproteins (mucins) and serum immunoglobulins

Steriod hormones and their various metabolites

Drugs, toxins, and heavy metals

Amino acids, peptides and Vitamins

Term
bile canaliculi eventually becomes
Definition
hepatic bile ducts which ends in a common hepatic duct
Term
Common bile duct picks up the main pancreatic duct at
Definition
ampulla of vater
Term
Ring of circular smooth muscle that is the exit of the biliary system immediately before entering the duodenum
Definition
Sphincter of Oddi
Term
Gallbladder's lateral walls are relatively impermeable to_____ leading to the standing osmotic gradient
Definition
Na
Term
What are bile acids?
Definition
potent amphipathic organic acid detergents made from cholesterol, with pKa's near neutral and usually associated with sodium as bile salts
Term
Hepatocytes conjugate bile acids with ____ or _____ thereby lowering the pKa of the conjugated bile acids
Definition
glycine or taurine
Term
Primary bile acids
Definition

cholic acid and chenodeoxycholic acid

directly synthesized from cholesterol

Term
Secondary bile acids
Definition

formed by the action of intestinal bacteria on the primary bile acids (rmove OH)

3.5 grams

Term
Excretory mixed micelle
Definition
formed when lecithin enters a micelle
Term
absorptive micelles
Definition
occur when micelles enter the duodenum and pick up the hydrophobic components of the diet and products of lipid digestion (FFA's, 2MG)
Term
lipid soluble contents of micelles are absorbed via
Definition
the unstirred layer on the microvilli surface of the epithelium of the mid-jejunum
Term
non lipid soluble contents of micelles are absorbed via
Definition
across apical membrane of ileal enterocytes via either a Na-independent transporter protein, OATP1B1, or a 2:1 Na-BS cotransporter alpha and betat and the ATPase transporter, MRP3
Term
Bile pigment formed in
Definition
reticuloendothelial cells located throughout vasculature
Term
pump used to transfer bilirubin into the cell
Definition
OATP1B1 (also carries BS)
Term
Chemoreceptors that sense toxins, and trigger vomiting are located
Definition
near the floor of the fourth ventricle of the brain and in the gastric and duodenal mucosa
Term
Bilirubin conjugated with two glucuronic acids in the SER of a hepatocyte to form
Definition
bilirubin diglucuronice
Term
Bilirubin diglucuronice (BRDB) is actively pumped out of the hepatocyte and into the bile canaliculi by:
Definition
multidrug-resistance related protein 2 (MRP2)
Term
Gives urine and feces their color
Definition
Urobilinogen
Term
Jaundice
Definition
accumulation of >1.5 mg% total bilirubin in blood
Term
Prehepatic jaundice
Definition
excessive bilirubin production overwhelming the capacity of a healthy liver to take up and conjugate the BS
Term
Hepatic jaundice
Definition
results from a decrease in functional liver cells (e.g intoxication or infection of the liver as with hepatitis virus) making it unable to handle the normal load of BS
Term
Posthepatic jaundice
Definition
obstruction in the biliary tact (eg cholelithiasis) with pressure back up and regurgitation of conjugated BS out of the biliary tract and into the blood
Term
Used to import conjugated and unconjugated BS on the hepatocyte sinusoidal membrane
Definition

Na-dependent, Na-taurocholate-co-transporting polypeptide=NTCP

Na-independent organic anion-transporting peptide=OATP1B1

Term
OATP1B1 found
Definition

-hepatocyte sinusoidal membrane

-apical membrane of ileal enterocytes to import BS

Term
Na-independent OATP1B3 transporter imports
Definition
bile jpigment, glutathione, bromosulphonphthalein and various radiopaque dyes
Term
Transporters on the hepatocyte sinusoidal membrane
Definition

NTCP

OATP1B1

MRP3- ATP-dependent multidrug resistance-related protein 3

Term
ATP-dependent multidrug resistance-related protein 3 transports
Definition

organic solutes into the hepatocyte

(MRP3 is also on the BLM of ileal enterocytes where it exports BS out of the cell and into the body)

Term
Transporters that transport from the hepatocyte to the canliculi
Definition

BSEP

MRP2

MDR1

MDR3

(all are ATPases belonging to the ATP binding cassette)

Term
BSEP transports
Definition

monovalent BS

(bile salt export protein)

Term
MRP2 exports
Definition
divalent BS, bile prgment, glutathione, cystic fibrosis transmembrane conductance regulator, bromosulphonphthalein and various radiopaque dyes
Term
MDR1 exports
Definition
organic cations and xenobiotics
Term
MDR3 exports
Definition
phospholipids like lecithin
Term

The

 

cholangiocyte

basolateral membrane (BLM) contains:

Definition

 

 

 

A) a Na

+-hydrogen exchanger 1 (NHE 1) that exports H+ in exchange for Na+ entry.

B) a Na

+- HCO3

-

 

co-transporter.

C) a Na

+- K+-2Cl- co-transporter.

D) the usual K

+ channel.

Term
Cholangiocyte canalicular membrane contains
Definition

CFTR Cl channel

Ca activated Cl channel

AE2

Term
AE2 funciton on canlicular membrane
Definition
exports HCO3 being driven by the Cl gradient thereby alkalinizing the bile
Term
Apical transporters typically generate what kind of gradient
Definition
-6 mV with a negative lumen
Term
Importers of BS in ileum enterocytes on apical membrane
Definition

OATP1B1

ASBT (electroenic apical sodium dependent BS trasporter)

Term
Exporters of BS on the basolateral membrane of ileum enterocytes
Definition

MRP3

the heterodimeric organic solute transporter alpha and beta, OSTalpha and beta

Term
Substances that stimulate bile flow
Definition
choleretics
Term
Secretin affect on bile flow
Definition
stimulates bile flow
Term
The release of ATP into the bile vy cholangiocytes activates
Definition

purinergic P2 (P2Y2) receptors on the cholangiocyte surface that results in an increase in intracellular Ca through a mechanism involving conventional or novel PKC

Elevated Ca opens Ca activated Cl channels

Term
Cl exchanges for HCO3 bile to cholangiocytes via
Definition

AE2 exchanger

results in dilution and alkalinixation of the bile

Term
ATP released by shear of flow affect on bile flow
Definition
stimulates
Term
Cephalic phase of digestion stimulus
Definition
taste and smell of food, food in mouth and pharynx
Term
CCK secreted in the stomach by fat digestion acitvation does what involving bile?
Definition

causes the gallbladder to contract strongly, increases common bile duct peristalsis and further relaxation of the sphincter of Oddi

Term
Acid in chyme evokes the release of _____ from duodenal enteroendocrine cells
Definition
the hormone secretin
Term
Secretin stimulates
Definition
increased bicardbonate secretion from all the pancreatic and common bile duct epithelial cells and the walls of the small intestine
Term
Choleretic effect
Definition

as bile acids are actively absorbed in the ilium, the

elevated blood levels stimulate further bile secretion by hepatocytes

Term
Higher blood bile acids act in an inhibitory fashion on
Definition
the first enzyme (7-alpha hydroxylase) in the conversion of cholesterol into bile acids
Term
Mediating factor of intestinal digestion
Definition

cholecystekinin

Secretin

High concentration of bile acids in portal blood

Term
Mdiating factor in interdigestive period
Definition
low concentration of bile acids in portal blood
Term
Stimulus of intestinal digestion
Definition

fat digestion products in duodenum

Acid in duodenum

Absorption of bile acids in the distal part of ileum

Term
Stimulus of interdigestive period of digestion
Definition
low rate of release of bile to duodenum
Term
NTCP brings in
Definition
conj. BS
Term
OATPs
Definition
conj and unconj BS
Term
OCTI carries in
Definition
organic cations
Term
MRP3 carries
Definition
organic solutes
Term
SPGP or BSUP excrete
Definition
monovalent BS
Term
MRP2 mediates organic anion export of
Definition
divalent BS, BRDG, and glutathione
Term
MDR1 excretes
Definition
organic cations and xenobiotics
Term
MDR2 on the CM of hepatocyte transports
Definition
phopholipids ie lecithin
Term
AE2 exchanges
Definition
HCO3 (exits) with Cl (enters)
Term
OATP1B1 on apical/luminal membrane of enterocytes in the ileum brings in
Definition
BS
Term
ASBT brings in
Definition
BS
Term
FXR has what effect on bile salt import proteins in elevated bile salt concentrations
Definition
represses bile salt important proteins, while activating the genes for the BS exporting proteins on the basolateral membrane
Term
FXR reduces the potential of systemic infection by
Definition
maintaining the mucosal defense barrier and protecting the lower intestinal epithelium against bacterial overgrowth
Term
Reduce liver cell destruction in cholestasis by
Definition
inhibition of the human cholesterol-7-alpha-hydroxylase gene promoter CYO7A1 by administration of Fibroblast Growth Factor 19 possibly via FXR
Term
unabsorbed bile salts int he colon produce
Definition
osmotic diarrhea, steatorrhea and loss of calcium and fat-soluble vitamins
Term
Vomiting center located
Definition

fasciculus solitarius in the dorsolateral border

of the lateral reticular formation of the medulla

Term
Chemoreceptor trigger zone for vomiting located in
Definition
above medulla in the area postrema on the floor of the 4th ventricle
Term
During retching intrathoracic pressure is
Definition
dramatically lowered
Term
During retching, intra-abdominal pressure is
Definition
raised due to abdominal muscles strongly contracting
Term
During retching stomach acid secretion ____ while mucus and salivary secretions _____
Definition

decreases

increases

Term
Electrical stimulation of vomiting center results in
Definition
projectile vomiting without retching
Term
Caudal half of colon receives innervation by
Definition
pelvic nerve parasympathetic preganglionic fibers
Term

proximal colon receives sympathetic postganglionic nerve fibers from the

Definition
superior mesenteric ganglion
Term
the distal colon recieves sympathetic postgangionic nerve ffibers from
Definition
the inferior mesenteric ganglion
Term
the rectum and anal canal are innervated by sympathetic fibers from
Definition
hypogastric plexus
Term
The striated muscle comprising the external anal sphincter is innervated by
Definition
somatic fibers in the pudendal nerves
Term
During defecation muscles of the pelvic floor
Definition
relax
Term
In addition to the ENS, the defecation reflex is coordinated by:
Definition
a spinal cord center which is facilitated or inhibited by the cerebral cortex
Term
Gastrin influence on defecation
Definition
increases motility of the ileum and relaxes the ileocecal sphincter
Term
Epinephrine effect on defecation
Definition
inhibits colonic motility and the prostaglandin E's decrease segmentation and increase peristalsis
Term
examples of osmotic diarrhea
Definition

Lactose intolerance; sea water; MgSO

 

4; steratorrhea; post-prandi, aldumping syndrome

Term
secretor diarrhea examples
Definition

 

Bacterial toxins e.g., cholera (cAMP mediated Cl

 

 

-

secretion);

enteropathic E.coli (

 

 

↑[Ca++]

i); Gastrinoma; VIPoma

Term
malabsorptive diarrhea examples
Definition
 bile acid malabsorption, gluten enterophathy, cholelithiasis
Term
Exudative diarrhea examples
Definition

Invasive organisms e.g., salmonella, amoeba histolytica, withinflammation and blood loss; influenza; Crohn’s Disease (ileitis);ulcerative colitis

Term
Excess motor activity diarrhea examples
Definition
IBS, bacterial action on unabsorbed long-chain fatty acids, stress
Term
Results of chronic diarrhea
Definition
dehydration, hypokalemia, and acidosis, loss of water soluble vitamins, possible loss of Ca and fat soluble vitamins
Term
Hirschsprung's disease
Definition
absence of ENS in the internal anal sphincter and often rectum
Term
Diverticula
Definition

outpouchings of the mucosa through the muscular wall of the colon

maybe due to chronic high intraluminal pressure

Term
Mucosal transporters in jejunum and ileum
Definition

NHE- Na and H antiport

Na and gluc (a.a.) symport

K and Cl symport

H20

Term
Serosal transporters in jejunum and ileum
Definition

Na and K ATP dependent antiport

facilitated gluc (a.a) transporter

Facilitated Cl transporter

H20

Term
Mucosal transporters in ileum and colonbut not jejunum
Definition

HCO3 and Cl antiport

Epithelial Na channel

Term
Serosal transporter in ileum and colon but not jejunum
Definition
NBC transporter- HCO3 and Na antiport
Term
Colon does not have which transporter
Definition
Na and gluc (a.a.) symport
Term
Colon does have which transporter that the small intestine does not
Definition
K and H antiport ATP dependent
Term
Myenteric plexus is the same as:
Definition
Auerbach's plexus (motor control of the longitudinal and circular muscles)
Term
Parietal cell the same as:
Definition
Oxyntic cell (secretes stomach acid)
Term
Gastrin-releasing peptide is the same as
Definition
GRP or bombesin (vagal mediator of gastrin release)
Term
isomaltase is the same as
Definition
alpha-limit dextrinase (exzyme at the surface of small intestine brush border)
Term
fastric inhitory peptide is the same as
Definition
glucose insulatropic peptide (during the intestinal phase of digestion these block acid secretion and increase insulin release)
Term
Effect of Gastrin
Definition

increase acid

increase acid sec mucosa

Term
Effect of CCK
Definition

increase in bicarbonate and enzyme gallbladder contract

decrease in gastric emptying

decrease in appetite

increase in insulin

Term
Effect of secretin
Definition

increase of bicarbonate and fluid

decrease in acid

increase in cAMP via activation of AC

Term
Effect of GIP (gastric inhibitory peptide)
Definition

decrease in acid

increase in insulin

Term
Effect of VIP
Definition

increase intestinal secretions

Relaxes smooth muscle

Term

Effect of GRP

 

Definition
Increase gastrin sec
Term
Effect of enkephalins
Definition
decrease intestinal sec
Term
Effect of somatostatin
Definition

decrease acid

decrease gastrin sec

decrease insulin

Term
Effect of histamine
Definition
increase acid
Term
Neurocrines involved in GI control
Definition
VIP, GRP, Enkephalins
Term
Paracrines involved in GI control
Definition

somatostatin

Histamine

Term
Somatostatin blocks
Definition
production of gastrin
Term
antral contractions block
Definition
gastric parietal cell and production of gastrin
Term
dipeptidyl peptidase reduces ____ to _____
Definition
oligopeptides to dipeptides
Term
calmodulin regulates
Definition
serosal Ca-ATPase
Term
Calcium binding protein
Definition
calbindin
Term
Iron absorption highest in:
Definition
duodenum and first part of jejunum
Term
Iron primarily absorbed in what form?
Definition
ferrous
Term
In blood iron is bound to:
Definition
transferrin
Term
Siderosis
Definition
abnormal iron accumulation that exceeds iron excretory capacity
Term
Heamochromatosis
Definition
genetic defect producing iron accumulation in vital organs, most seriously in the heart causing cardiomyopathy
Term
Vitamin B12 is carried around circulatory system by
Definition
transcobalamin II
Term
Most to least salivary secretions at high flow rate
Definition

Na

HCO3

CL

K

Term
Most to least gastric secretions at high flow rate
Definition

Cl

H

K

Na

Term
Most to least pancreatic secretions at full flow rates
Definition

Na

HCO3

Cl

K

Term
absorption is regulated by diet except for
Definition
Ca and iron
Term
crypt cells mature and migrate toward tip of vilus to become
Definition
villus cells
Term
jejunum is important site for absorption of
Definition
sugar and a.a.
Supporting users have an ad free experience!