Physio Main Ideas Flashcards
autoimmune, attacks salivary and lacrimal glands
sjogren syndrome
xerostomia
dry mouth
as saliva rate increases, which ion concentration increases
chloride
(SNS/PNS) drives salivation
mainly PNS
pepsinogen becomes active at (low/high) pH
low pH
____ ____ can result from chronic use of NSAIDs, which inhibit prostaglandin synthesis in the stomach which is supposed to stimulate secretion of mucous and HCO3-
erosive gastritis
alkaline tide controlled by which cells
parietal cells–push base into blood
enzyme involved in alkaline tide
carbonic anhydrase
prolonged _____ causes dehydration, alkalosis, and hypokalemia (low K)
vomiting
stimulators of HCl secretion by parietal cell (three)
vagus-ACh, gastrin, histamine
why does an H2 receptor blocker prevent ulcer formation
prevents histamine from stimulating acid secretion by parietal cells
why does atropine prevent ulcer formation
prevents ACh from vagus stimulation from stimulating acid secretion by parietal cells
why does omeprazole/proton pump inhibitor prevent ulcer formation
prevents final common pathway in HCl release by parietal cell
low pH in stomach (inhibits/stimulates) somatostatin production
stimulates
which nerve mediates the cephalic phase of digestion
vagus
myenteric/Auerbach’s plexus is (between circular muscle and submucosa/between longitudinal muscle and circular muscle) layers
between longitudinal muscle and circular muscle
Auerbach’s plexus controls (secretions/contractions) of gut
contractions (meyenteric=motor)
submucosal/Meissner’s plexus is (between circular muscle and submucosa/between longitudinal muscle and circular muscle) layers
between circular muscle and submucosa
Meissner’s plexus controls (secretions/contractions)
secretions (submucosal=secretions)
gut go signal: (ACh/Norepi and epi)
ACh
gut stop signal: (ACh/Norepi and epi)
Norepi and epi
pacemaker cells in the gut
interstitial cells of Cajal
contractions that maintain a constant tone of the gut without regular periods of relaxation
tonic contractions
APs in the gut are stimulated by (three things)
stretch, ACh release, parasympathetics
myenteric reflex
peristalsis
NO causes what in the gut
relaxation of vessels supplying circular muscle
contraction of circular muscles controlled by ACh and _____
Substance P
absence of motility in small and large intestine
physiological ileus
extra long periods of no motility in the gut, common after abdominal surgery or opiate drug treatment
pathological (paralytic) ileus
function of MMC
periodic sweep to remove junk
disorders of swallowing occur with damage to which three CNs
V, IX, X
three ways to get disorders of swallowing
infection, CN damage, anesthesia
receptive relaxation occurs in the (proximal/distal) stomach with each bolus of food
proximal
high fat meals: (faster/slower) gastric emptying
slower
clinical correlation: lower esophageal sphincter can’t relax
Achalasia–necrosis of esoph mucosa, too tight
clinical correlation: lower esophageal sphincter tone is not maintained, too loose
GERD–esoph is not protected from acid of stomach
clinical correlation: pancreatic cancer that results in watery diarrhea
VIPoma (VIP is an NT that doesn’t do much except when there is a tumor)
clinical correlation: cause of fatty stool
Cystic Fibrosis–Cl- channel defect
secreted fluid from the pancreas is (high/low) in HCO3- at fast rates of secretion
high
type of receptor on acinar and duct cells
M3 muscarinic cholinergic
clinical correlation: a blocked sphincter of Oddi could cause
pancreatitis
bile salt reabsorption is a way to reduce _____
cholesterol
patients who get their terminal ileums removed cannot use the terminal ileum to reabsorb ____
bile salts
clinical correlation: gall stones precipitate when which three things get out of whack
cholesterol, bile salts, lecithin
alpha cells are in the (center/periphery) of the islet of Langerhans
periphery
beta cells are in the (center/periphery) of the islet of Langerhans
center
blood flow in the islet of Langerhans is from the (outside in/inside out)
inside out, so insulin can inhibit glucagon secretion
which transporter brings glucose into muscle and fat cells
GLUT4
glucagonoma causes (hyper/hypo) glycemia
hyperglycemia
insulinemia caused by over treatment has (high/normal) levels of C peptide
normal
insulinemia caused by insulinoma has (high/normal) levels of C peptide
high
insulinemia causes (hyper/hypo) glycemia
hypoglycemia
lesion of lateralhypothalamic area causes (aphagia/hyperphagia)
aphagia
lesion of ventromedial nucleus causes (aphagia/hyperphagia)
hyperphagia
leptin and leptin receptor mutations cause ____ in humans and mice
obesity
clinical correlation: how much of the SI can be removed without compromising absorptive function
half
clinical correlation: autoimmune, reduces # of villi, SA of SI goes down
celiac sprue
clinical correlation: reduces # villi, diarrhea, malabsorp, caused by infection
tropical sprue
clinical correlation: why does radiation therapy make you nauseous
kills rapidly dividing cells first, intestinal cells have quick turnover
clinical correlation: pernicious macrocytic anemia
Vit B12 def, can’t absorb in terminal ileum
vipoma increases ____ in the crypt cell of the jejunum, opens the CFTR channel, leads to excess Cl- secretion into lumen, water follows
cAMP
cholera toxin increases cAMP in the crypt cell of the jejunum and causes:
watery diarrhea–CFTR channel, Cl- flows into lumen, water follows, horrible dehydration
how does oral rehydration work for cholera
give Na/glucose/water solution so Na will enter cell with the sugar and cause restoration of water balance
we can only absorb iron in which form
Ferrous Fe2+
clinical correlation: too much iron absorption, iron is deposited where it doesn’t belong
congenital hemochromatosis
how is iron reduced from ferric to ferrous so we can absorb it
by acid in the stomach
role of transferrin
transports iron in blood
most efficient way for iron to be absorbed: (heme/non heme)
heme (source: red meat)
non heme iron is absorbed via cotransport with a ____
proton
clinical correlation: system B apical membrane aa transporter is defective, neutral aa absorption is limited, also in kidney
Hartnup disease
clinical correlation: which aa’s are not absorbed in Hartnup disease
Phe
clinical correlation: excessive amounts of which aa is excreted in the urine in Hartnup disease, and what is that aa a precursor of
Trp–serotonin, melatonin, niacin
clinical correlation: system B0+ apical membrane aa transporter is defective, L-cysteine and basic aa absorption is reduced, kidney stones
cystinuria
(GLUT5/SGLT1) how glucose and galactose enter enterocyte
SGLT1
(GLUT5/SGLT1) how fructose enters enterocyte
GLUT5
(GLUT5/SGLT1) Na+ dependent, so monosaccharides absorbed can be concentrated inside enterocyte
SGLT1
(GLUT5/SGLT1) Na+ independent, so monosaccharides absorbed cannot be concentrated inside enterocyte
GLUT5
in lactase def, colonic bacteria metabolize the lactose resulting in higher __ excretion
H2 (exhaled)
SGLT1 def is very (rare/common)
rare
treatment of SGLT1 def
fructose is only sugar in diet
fat digestion occurs mostly in the (duodenum/jejunum/ileum)
jejunum
which organelle in the enterocyte is responsible for reesterification of fats
SER
apoprotein ___ essential for formation of chylomicrons
B48
automatic, uninhibited, spastic neurogenic bladder: (LMN/UMN) problem
UMN
clinical correlation: causes distended bladder with overflow incontinence and dribbling and predisposition to infection
LMN neurogenic bladder
autonomous, motor, sensory neurogenic bladder: (LMN/UMN) damage
LMN
clinical correlation: common in older men, frequent urination, dribbling, weak stream, urgency
enlargement of prostate, benign prostatic hyperplasia/hypertrophy
fiber (increases/decreases) movement through colon
increases (avoid constipation)
(excess/deficient) motility in colon causes less absorption and diarrhea/loose feces
excess
(osmotic/secretory) diarrhea: results from non-absorbable solutes in lumen (lactase def)
osmotic
(osmotic/secretory) diarrhea: results from excessive secretion of fluids by crypt cells due to bacterial overgrowth
secretory
the _______ prevents backflow from colon to ileum, emptying is regulated by stretch, chyme
ileocecal sphincter
clinical correlation: gastric pain followed by vomiting, fever, left untreated= ischemia and tissue necrosis can lead to peritonitis, septicemia, death
appendicitis
colon (absorbs/secretes) Na and Cl
absorbs (also water)
colon (absorbs/secretes) K and HCO3
secretes
the key determinant of water reabsorption in the color is the rate of __ (ion) absorption
Na
exchangers for __ (ion) absorption and __(ion) secretion are prominent in the proximal colon: major means of salt and water reabsorption in colon
Na/HCO3 exchangers
aldosterone (increases/decreases) number of epithelial Na channels in colon
increases
how is Na extruded from epithelial cell of colon into the blood
Na/K/ATPase
clinical correlation: individuals with ulcerative colitis have (fewer/persistent) mass movements in the colon
persistent–due to irritation in the colon
clinical correlation: a segment of the colon is permanently contracted and results in obstruction
Hirschprung’s disease/megacolon
clinical correlation: ____ results from a lack of ENS in distal part of GI tract (aganglionosis)
Hirschprung’s
clinical correlation: treatment for Hirschprung’s
remove aganglionic segment
___ is an important signal of bowel activity, and is often documented after surgery
flatulence
bacteria comprise __% of dry weight of feces
10%
clinical correlation: common GI disorder, crampy pain, bloating, gassiness
IBS
clinical correlation: treatment of symptoms for IBS diarrhea predominant cases
opioids and serotonin receptor antagonists
clinical correlation: treatment of symptoms for IBS constipation predominant cases
serotonin agonists, soluble fiber
stand up»_space; mass movement
orthocolic reflex
eat big meal»_space; mass movement
gastrocolic/duodenocolic reflex
myenteric reflex in colon
increases peristalsis wen rectum distends, relax internal sphincter