Physio PA of Digestive System

_______________ takes place in mouth stomach and SI while ___________ takes place in SI

digestion nutrient absorption

teeth, tongue, salivary glands, liver, gallbladder, pancreas

accessory organs of digestion

tongue is made of _________ innervated by

skeletal m hypoglossal nerves

papillae

taste buds, cover tongue and filled with gustatory cells

gustatory cells

sensory receptors within a taste bud w/ pore for nerve signals

taste bud impulses transmitted by _______________ nerves to taste areas:

facial + glossopharyngeal (7 + 9) parietal-temporal cortex

location of ____________ at parotid, submandibular and sublingual

major and serous salivary glands

location of ____________ at labial, buccal, glossopalatine, palatine and lingual

minor salivary glands

serous salivary glands secrete

ptyalin - a-amylase to digest starches

mucous salivary glands secrete

mucin - lubrication + protection

acinar cells of salivary gland

produces initial saliva

how do the ductal cells of salivary gland modify the initial saliva

alters conc of electrolytes

myoepithelial cells of salivary gland

in acini and intercalated ducts, contract to eject saliva to mouth

how does saliva buffer food

acidic foods buffered by bicarbonate ions

GFs in saliva role

epidermal GFs heal ulcers in mucous membrane of mouth

lysozyme role in saliva

enzymes destroy bacteria - non specific immune defense

___________ is ph 6-7

saliva

which innervation control is dominant in saliva secretion

parasympathetic (high blood flow increases saliva)

saliva is made from

blood plasma

2 stages of salivary secretion

1 - acinar cell secretes NaCl rich primary saliva = isotonic 2 - primary saliva modified along ductal tree - hypotonic (permeable to water)

flow rate of saliva change as

ionic composition changes, depending on contact w/ ductal cells

under which conditions is saliva most similar to plasma

during maximal salivation (least modification)

what is different about HCO3- in composition of saliva

secreted by ductal cells, highest conc at high flow rates

how is salivary ph differentiated for viewing

w/ methyl red + bromo blue

salivary cotinine test

determines exposure to nicotine, immunoassay w/ monoclonal atb coated gold + traps

level 1 in salivary cotinine test demonstrates what

use of tobacco

alcohol salivary test (AST)

qualitative, detects ethyl alcohol, line if greater than 0.02% BAC

where are mucins secreted

mucous neck cells of gastric glands by surface epithelial cells of stomach

mucus gel is subject to ______ by pepsins which dissolves the mucus layer

proteolysis

what protects stomach lining

mucus + HCO3-

how does h. pylori manifest

antral gastritis

flagella, urease, adhesins, toxins are features that help the virulence of what

h. pylori

chronic antral h. pylori gastritis may progress to

pangastritis + intestinal metaplasia

urea breath test tests what

h. pylori's production of urease

what are h. pylori stool antigen tests used for

diagnosis and confirmation it was cured

positive test of IgA H. pylori

C + T lines present

what does IgG ini h. pylori not distinguish

bw previous exposure and acute infection

___________ diagnoses GORD and treats ulcers + polyps, for finding and treating cause of bleeding

EGD

how are biopsies performed in endoscopy

at least 3 sites in stomach + duodenum, atb avoided

best time to take rapid urease test

at time of gastroscopy

culture from endoscopy biopsy allows determination of

atb susceptibility

internal structure of pancreas is similar to that of

salivary glands

pancreatic juice

protein rich alkaline secretions

pancreatic digestive enzymes are secreted by pancreatic ____________, and large volumes of _______________ are secreted by the small ductules and larger ducts leading from the acini

acini sodium bicarbonate solution

pancreatic secretions flow to join hepatic duct and empties into ________ via _________-

duodenum thru Vater papilla, surrounded by sphincter of Oddi

each secretory unit of the pancreas is composed of

acinus + intercalated duct

pancreatic juice is secreted in response to

chyme presence in SI

___________ consists of inflammation and interstitial edema -> necrosis

acute pancreatitis

symptom of acute pancreatitis

severe epigastric and abd pain radiating to back

causes of acute pancreatitis

gallstones + alcohol abuse

lab tests for acute pancreatitis

serum amylase + lipase increased

in contrast to acute pancreatitis, the serum amylase and lipase levels are usually ________________ in chronic pancreatitis, additionally bilirubin and alkaline phosphatase are high

mildly elevated

hormone stimulation test for chronic pancreatitis utilizes

secretin

what are ERCP and MRCP tests used for

chronic pancreatitis

The most characteristic symptom of gallstone disease is

biliary colic

what serum elevations suggest cholestasis

bilirubin + alkaline phosphatase

inflammation of acute cholecystitis can spread, leading to irritation of gallbladder and dev of

empyema -> sepsis

digestion test

exam of stool w/ saline + Sudan III for lipid detection, Lugol for starch

gallbladder insufficiency, bowel movements and bad absorption in a digestion test are suggested how

high amounts lipids

in digestion test, what does increased muscle fibers suggest

pancreatic insufficiency and gastric hyposecretion

starch (reddish) in digestion test stool is related w/

carb consumption + high intestinal transit

stool w/ leukocytes is seen in ___________ and needs follow up culture

infections

Charcot-Leyden crystals can be present in case of

parasitosis

Schilling test

for cobalamin malabsorption (pernicious anemia, pancreatitis)

The Fecal Occult Blood Test (FOBT)

detects blood in stool not visible, using double ATB sandwich assay not affected by diet

red meat and drugs (NSAIDs, aspirin, steroids) cause false positives in which test

FOBT

___________ are for bleedings, inflammatory rectal disease + colorectal cancer

sigmoidoscopy

clinical application of VCE (video capsule endoscopy) is

evaluation of GI bleeding

__________ is an autoimmune disorder of SI caused by rxn to gliadin by transglutaminase

celiac disease

Antiendomysial antibodies of the immunoglobulin A (IgA) is what

serological test for celiac

2 types of IBD

UC (autoimmune) and CD (genetic)

elevated CRP, PLT, ESR and less HB are in which diseas

ulcerative colitis

which test is used to assess UC

sigmoidoscopy

elevated ESR, CRP, hypoalbuminemia and anemia are suggestive for which disease

CD

liver is an organ with what type of structure

parenchymal structure

what is needed to diagnosis a hepatic patho

history + examination, but also advanced imaging + biopsy

hepatocytolysis syndrome

hepatocyte membrane dysfxn, enzymes leak into plasma

___________ are diagnosed by increased transaminases + LDH

hepatocytolysis syndrome

diff vs GOT and GPT

GOT is not specific, GPT is for hepatic lesions

acute vs chronic hep

acute has high increase of ALT + AST

Rittis ratio in chronic alcohol consumption

AST/ALT, increased in alcohol related patho, lower is hep

cholestatic syndrome

bile flow impaired from obstruction or atb

alkaline phosphatase + GGT are elevated in which syndrome

cholestatic syndrome

_____________ maintain oncotic p and assure normal clotting + gluconeogenesis

proteins of liver

most sensitive test for analyzing hepatocyte fxn (ex hepatodeficiency syndrome)

coag test - analyzes albumin, INR + glucose

inflammatory syndrome, seen in acute hep, shows high inflammatory markers and increase in

gamma globulins conc

jaundice can be classified as

pre, post and hepatic

___________ is represented by increased bilirubin production (rbc hemolysis) + total bi

prehepatic jaundice

hepatic jaundice

liver can't metabolize bi

Crigler-Najjar syndrome (neuro impairment) + Gilbert syndrome are associated w/ which type of jaundice

hepatic jaundice

type I vs II Crigler-Najjar

I (recessive) no glucuronyltransferase

mechanism of Dubin-Johnson + Rotor syndrome (hepatic jaundice)

transportation of conj bi impaired, dark spots on liver in Dubin Johnson

neonatal hepatic jaundice

limited phase after birth bcus glucuronyltransferase enzyme is not matured or breastfeeding

posthepatic jaundice

obstruction of bile ducts, increased conj bi