GI Questions
Select the FALSE statement regarding gastric secretions. A. Pepsinogens are cleaved to pepsins in the acid enviornment, and begin carbohydrate digestion B. Antral gastrin release is increased by distension of the stomach and vagal stimulation C. Gastric lipase is inactivated in an alkaline enviornment D. Mucus secreted by the surface mucous cells acts to protect the gastric mucosa from the low pH E. Somatostatin acts in a paracrine fashion to inhibit HCl secretion, while histamine stimulates HCl secretion
A.
Select the FALSE statement regarding the basal electrical rhythm (slow waves). A. Slow waves are hyperpolarized by stretch, ACh, gastrin, and substance P B. The rate of slow waves varies through the GI tract C. Action potentials are generated on top of the slow waves, and cause the contractions D. The BER controls the rate of propulsion of chyme through the intestines E. Slow waves are undulations in resting membrane potential caused by variations in Na+/K+ ATPase activity
A.
Select the FALSE statement. During protein digestion A. Peptides in the duodenum stimulate CCK release, which increases gastric HCl B. In the enterocyte, cytoplasmic proteases break down di- and tri- peptides into amino acids C. Trypsin inhibitor is secreted into the hepatic ducts to prevent autodigestion D. Pepsinogens are secreted by the chief cells in response to stimulation by gastrin and ACh E. Trypsin activates chymotrypsinogen, trypsinogen, and procarboxypeptidase
A.
Select the FALSE statement. The migrating myoelectric compex (MMC) is A. Dependent on the vagi B. Propagated in part by the enteric nervous system C. A means of removing intestinal bacteria D. Present from the stomach through the ileum E. Similar to a mass movement in that both extend for a considerable distance
A.
Select the FALSE statement. The unstirred water layer lining the gastrointestinal tract A. Is readily permeable to amino acids, glucose and lipids B. Protects the mucosa from damage C. Normally maintains a pH of -7 next to the epithelial cells D. Can be penetrated by helicobacter pyloru E. Can be disrupted during episodes of diarrhea
A.
Select the TRUE statement A. Vagal stimulation increase HCl secretion and stimulates mass movements in the colon B. Gastrin stimulates pancreatic activity electrolyte secretions and increases antral motility C. Secretin can potentiate the effects of ACh to increase pancreatic enzyme secretion because they work through the same second messenger system D. GIP is secreted in response to fats and glucose and acts to increase HCl secretion and decreas gastric empyting E. ACh acts through a cAMP pathway to stimulate pepsinogen secretion in the stomach
A.
Select the TRUE statement regarding gastrointestinal motility. A. Segmental propulsion through the colon is very slow B. The migrating myoelectric complex is stimulated by ingestion of food C. During the rectrosphincteric reflex, the internal anal sphincter is contricted D. Peristalsis pushes chyme over long sections of the intestines E. Colonic mass movements are stimulated by secretin
A.
Select the TRUE statement regarding ion handling by the gastrointestinal tract. A. Bicarbonate is secreted into the lumen of both the ileum and the colon B. Aldosterone administration decreases colonic sodium absorption C. Absorption of divalent cations favors high pH D. Calcium enters the enterocytes through passive diffusion E. Excess calcium in the intestinal lumen facilitates phosphate absorption
A.
Select the TRUE statement regarding protein digestions and adsorption. A. Brush border proteases degrade oligopeptides down to di- and tri- peptides and amino acids B. Protein digestions begins in the intestines by pancreatic proteases C. Each amino acids has a specific carrier D. Amino acid absorption into the enterocyte occurs through facilitated diffusion E. The majority of protein absorption occurs in the distal jejunum
A.
The absorption of vitamin B12 (cobalamin) in NOT dependent on A. The enterocyte vitamin B12 contraction B. R-binder in the saliva C. The integrity of the terminal ileum D. Vitamin B12/intrinsic factor binding sites on the enterocyte E. Secretion of intrinsic factor from gastric parietal cells
A.
The composition of saliva most closely resembles that of plasma when A. The parasympathetic nervous system is stimulated B. The sympathetic nervous system is stimulated C. The flow rate of secretion is low D. Meat is eaten E. There is increased secretion of dimeric IgA
A.
The concentration of sodium remians constant regardless of the flow rate in A. Pancreatic secretions B. Salivary secretions C. Gastric secretions D. Hepatic secretions E. Intestinal secretions
A.
The defecation reflex is triggered by A. Rectal distention B. Increased pressure on the external anal sphincter C. Release of norepinephrine from pelvic sympathetic neurons D. The migrating myoelectric complex E. Relaxation of the internal anal sphincter
A.
The excretion of bile in feces removes some of the cholesterol, bilirubin and random waste products from the body A. True B. False
A.
The primary factor determining the rate of bile acid and bile salt formation by hepatocytes is A. The amount of bile salts entering the portal blood B. The amount of fat entering the duodenum C. The plasma secretin level D. The activity of bacterial metabolism in the colon E. The adequacy of the lymphatic circulation in the gastrointestinal tract
A.
Which is the correct sequence that fatty acids and monoglycerides go through before being absorbed? A. Emulsion formation/micelle formation B. Micelle formation/penetration of the unstirred layer/emulsion formation C. Micelle formation/emulsion formation/penetration of the unstirred layer D. Emulsion formation/penetration of the unstirred layer/micelle formation E. Penetration of the unstirred layer/micelle formation/emulsion
A.
Which is the most important factor(s) affecting water movement through the gastrointestinal epithelium? A. Basolateral Na/ATPase B. Oligosaccharide movement C. An amino-acid transporter D. An apical chloride channel E. Carbonic anhydrase
A.
Which is the most important factor(s) affecting water movement through the gastrointestinal epithelium? A. Basolateral Na/K ATPase B. Oligosaccharide movement C. An amino-acid transporter D. An apical chloride channel E. Carbonic anhydrase
A.
Which of the following can be absorbed through sodium-dependent transport? A. Amino acids B. Short-chain fatty acids C. Vitamin B12 D. Fructose E. Vitamin A
A.
Select the TRUE statement A. Pancreatic lipase requires a colipase to access intestinal lipids B. The optimal pH for pepsin's enzymatic activity is -6 C. In chronic pancreatitis there is increased secretion of amylase and trypsin D. Disaccharidases are secreted from the crypts of Lieberkuhn E. Salivary a-amylase begins protein digestion in the mouth
A. B- incorrect-- pepsins are active in the stomach and catalytic activity is good at low pH (2-5)C- incorrect-- chronic pancreatitis would cause a reduction of both the exocrine and endocrine pancreas; thus, the enzymes that are secreted into the duodenum would be diminished (including amylase and trypsin).D- incorrect--disaccharidases are brush border enzymes and are located in the glycocalyx surrounding the tops of the villus cells.E- incorrect-- amylase digests starches.
In the enterocytes, reesterification of 2-monoglycerides with fatty acids occurs in the A. Smooth ER B. Cytoplasm C. Mitochondria D. Nucleus E. Endosomes
A. B-E are incorrect. Reesterification occurs in the smooth ER.
Which of the following sugars is taken into the enterocyte by facilitated diffusion? A. Fructose B. Glucose C. Galactose D. Maltose E. Gulose
A. Fructose enters the cells via the GLUT 5 transporter, which is insulin-independent.
Which hormone causes contraction of the gall bladder? A. Cholecystokinin B. Somatostatin C. Secretin D. Gastrin E. Insulin
A. Gallbladder contractions are stimulated by cholecystokinin-- the secretion of stored bile into the duodenum prepares the intestines for lipids.
Dietary lipid absorbed by the small intestine is transported out of the enterocyte through the interstitium directly A. Into lymph as chylomicrons B. Into lymph as free fatty acids C. Into blood as low-density lipoproteins C. Into lymph as low-density lipoproteins D. Into blood as chylomicrons
A. Lipids are packaged into chylomicrons in the enterocytes, and because of their large size they cannot enter capillaries, and instead enter lymph lacteals. They enter the systemic blood through the throacic duct into the left subclavian vein.
A 35-year old woman underwent a 55 cm ileal resection (normal ileal length is ~65 cm) because of ileal disease. After recovery from the operation the patient suffered from chronic diarrhea and mild steatorrhea (10g fat/day). She was treated with cholestyramine, which sequesters bile acids and prevents their function. This resulted in a dramatic reduction in her diarrhea and an increase in fecal fat content to 20g fat/day. Isotope studies revealed that her jejunal bile acid content was normal and that her daily excretion of bile acids was higher than normal values. The loss of ileal mass A. Reduces bile acid recycling B. Does not seriously affect intestinal digestion and absorption C. Does not seriously affect intestinal vitamin absorption D. Increases gastrin-induced jejunal motility E. Reduce the secretion of bile from the liver
A. Loss of the distal ileum will remove bile recycling, as well as vitamin B12 absorption. Absorption of electrolytes and fluids is also reduced because of the loss of absorptive area, and the presence of additional bile in the tract, which will exert an osmotic effect.
Gastric emptying is: A. Faster for hydrophillic lipids than for solid particles B. Accelerated by the presence of acid in the duodenum C. Slower for isotonic liquids than for hypo or hypertonic liquids D. Increased as the caloric content of the nutrients in the duodenum increase E. Faster for fatty chyme than for high fiber chyme
A. Non-fatty liquids will have the most rapid emptying from the stomach. As nutrient content increases, gastric emptying will slow, in general according to the increasing amounts of carbohydrates, proteins and fats (with carbohydrates being the most readily released into the duodenum).
Prior to absorption, proteins must be digested to A. Free amino acids, dipeptides, and tripeptides B. Free amino acids C. Polymers D. Pentapeptides and dipeptides E. Oligopeptides
A. Oligopeptides are digested to amino acids and di- and tri-peptides by the brush border proteases. These forms can then enter the cells through specific transporters.
Pancreatic gastrinomas (Zollinger-Ellison syndrome) A. Would be associated with decreased secretion of gastrin from gastric G-cells B. Are associated with hypoacidity of the duodenum C. Would decrease nutrient absorption because the enzymes in the pancreas are destroyed D. Would decrease secretin secretion E. Would decrease gastric somatostatin release
A
Protein digestion A. Involves pancreatic enzymes such as carboxypeptidase B and trypsin B. Begins in the stomach by both HCl and trypsin C. Would be severely impaired by removal of the colon D. Increases when the gastrocolic reflex is stimulated E. Occurs primarily in the ileum
A
A wrestler trying to "make weight" finds that he is a few grams over. In an attempt to lose the extra grams of weight, he sucks on a hard candy to induce copious salivation. The saliva he spits out A. Is relatively rich in sodium and poor in potassium B. Contains IgD C. Contains a peptidase that initiates protein digestion D. Is regulated primarily by sympathetic stimulation E. Is only under intrinsic regulation
A.
An alcoholic man with untreated, chronic pancreatitis would A. Have to depend primarily on salivary and gastric enzymes and HCl for digestion B. Have diarrhea with "rice water" consistency C. Have low levels of secretin D. Secrete normal levels of pancreatic have a-amylase E. Probably have normal levels of pancreatic ductal trypsin inhibitor
A.
Aunt Edna has a history of epigastric pain which is not periodic and not related to meals. It is relieved by antacids. She also has diarrhea and steatorrhea. Basal HCI secretion rate after an overnight fast was 25 mEq/hour, and this could be increased to 40 mEq/hour by the augmented histamine test. Radiologic examination revealed a gastric ucler. A high level of a "gastrin-like" substance was found in her plasma. Following surgical removal of a pancreatic tumor, her epigastric pain and diarrhea disappeared and her acid secretion was reduced. Select the FALSE statement: A. Edna's high rate of HCl secretion was due to hypersecretion of gastrin from her duodenl G-cells B. Edna's high rate of HCl secretion resulted in a low duodenal pH C. Secretion was acting at the pancreas to release a hydrelatic (electrolyte) solution D. Pancreatic enzyme activation was severely reduced in the duodenum E. Edna had osmotic diarrhea
A.
Bile forms the structure of the micelle A. True B. False
A.
Carbohydrate digestion A. In the stomach ends when HCl inactivates alpha-amylase B. In the colon converts starch to small oligosaccharides C. In the small intestine occurs by a single enzyme D. Is rarely so abnormal as to be clinically important E. Provides appreciable substrate for colonic bacteria
A.
During intestinal peristaltic propulsion A. Slow waves set he propulsive rate B. The direction of propulsion is always toward the anus C. Motor neurons distal to the bolus of chyme use VIP to contract the smooth muscle D. Motor neurons proximal to the bolus of chyme use tachykinin to relax the smooth muscle E. Antral systole can decrease when stimulated by stretch
A.
During intestinal peristaltic propulsion A. Slow waves set the propulsive rate B. The direction of propulsion is always toward the anus C. Motor neurons distal to the bolus of chyme use VIP to contract the smooth muscle D. Motor neurons proximal to the bolus of chyme use tachykinin to relax the smooth muscle E. Antral systole can decrease when stimulated by stretch
A.
During the infection with Vibrio cholerae A. The enterotoxin enters the enterocytes and stimulates cAMP, which increases chloride secretion into the lumen B. There is a massive parasympathetic discharge C. The enterotoxin enters the enterocytes and poisons the Na/K ATPase pump D. Plasma sodium contraction is very low E. The best treatment is an oral electrolyte solution of sodium chloride
A.
Fats are transported from the enterocyte to the blood primarily in the form of A. Chylomicrons B. Micelles C. Monoglycerides D. Free fatty acids E. Triglycerides
A.
For patients who do not respond to medical interventions for peptic ulcer disease, a complete removal of the gastric antrum may be considered. This would decrease gastric acid production by A. Eliminating a source of gastrin B. Reducing pepsinogen production by one-half C. Reducing the number of parietal cells by approximately one-half D. Eliminating the source of ACh E. Eliminating the source of histamine
A.
Gastric secretion of H+ A. Is regulated in part by the number of H+/K+ pumps B. Decreases in concentration with increasing gastric juice flow rate C. Comes from chief cells D. Is enhanced for lumenal sodium E. Is enhance by carbonic anhydrase inhibitors
A.
In the small intestine, peristaltic waves of contraction A. Involve contraction stimulated by tachykinin adoral (side near the mouth) to the bolus B. Cannot occur in the absence of parasympathetic innervation C. Involve receptive relaxation immediately aboral to the bolus of food D. Occur primarily in response to chemical stimuli from digested chyme E. Proceed in both directions from their site of origin
A.
In the stomach, receptive relaxation is caused by A. Entry of food B. Chyme in the intestine C. Relaxin D. A decrease in motilin E. Gastric inhibitory peptide
A.
Micelles taxi the digested lipids to the enterocytes A. True B. False
A.
Regarding pancreatic endocrine secretions A. Insulin can increase gastric motility and gastric secretions B. Glucagon can increase gastric motility C. GIP acts to decrease insulin secretion D. GIP acts to increase glucagon secretion
A.
Secondary bile acids A. Are formed by bacterial digestion of bile acids in the intestines B. Are derivatives of bilirubin C. Are formed by conjunction of a bile acid with glycine or taurine D. Are incorporated into mixed micelles in the gallbladder E. Do not enter the enterohepatic circulation
A.
Secretin A. Enhances pancreatic enzyme secretion by CCK B. Inhibits HCO3- secretion C. Speeds gastric empyting D. Increases bile acid secretion E. And CCk use the same second messenger system
A.
Select the FALSE statement concerning the colon A. Body potassium is conserved in diarrhea B. Stimulation by the luminal contents increases colonic mucus secretion C. Its enterocytes secrete bicarbonate D. Enteric reflexes stimulate its goblet cells to secret mucus E. Its bacteria acidify the inferior of the feces
A.
Gastric acid secretion is reduced: A. When acidic chyme enters the duodenum B. When pepsin is formed from pepsinogen C. When food stretches the corpus D. When intrinsic factor is secreted E. When the lower esophageal sphincter contracts
A. Regulation of gastric acid involves both stimulation of the parietal cells (ie, by gastrin, vagus, histamine) and inhibition of the parietal cell (somatostatin) or gastrin (by secretin and GIP). This modulation keeps acid secretion under control according to the amount and content of chyme.
What else is important about bile? (bilirubin metabolism/excretion)
Bilirubin that is secreted with bile is conjugated w/glucuronic acid Colonic bacteria remove the acid moiety and bilirubin is coverted to urobilinogen. About 10-20% of the urobilinogen is recycled into portal blood (from the colon) and then systemic circulation, where it is filtered, converted to urobilin (yellow color) and excreted in urine. The unabsorbed bilirubin is oxidized by bacteria to stercobilin (gives feces brown color) in colon. So "bilirubin" excretion occurs mainly in feces (as stercobilin).
Input from vagal efferent nerves to the gastrointestinal tract can A. Slow lower intestinal motility (e.g. ileum and proximal colon) B. Stimulate salvation C. Stimulate gastric parietal cells D. Slow contractions in the stomach E. Stimulate pancreatic insulin secretion
C.
Select the TRUE statement about lipid digestion and absorption A. Lipid digestion begins in the stomach with gastric lipase B. Lipids require a carrier protein to enter the intestinal cells C. Lipids are esterified with free fatty acids in the smooth endoplasmic reticulum (SER) D. Chylomicrons are made of lipids and bile E. All of the above are true
C.
Select the FALSE statement about electrolyte absorption in the intestines: A. Sodium absorption in the small intestine facilitates water absorption B. In the jejunum and ileum chloride can be absorbed in exchange for HCO3- C. In the colon, potassium is absorbed via BK channels D. In the jejunum and ileum sodium absorption is faciliated in exchange for H+ E. In the colon, aldosterone stimulates luminal sodium absorption via ENaC
C. Potassium is secreted into the lumen of the colon
A 35-year old woman underwent a 55 cm ileal resection (normal ileal length is ~65 cm) because of ileal disease. After recovery from the operation the patient suffered from chronic diarrhea and mild steatorrhea (10g fat/day). She was treated with cholestyramine, which sequesters bile acids and prevents their function. This resulted in a dramatic reduction in her diarrhea and an increase in fecal fat content to 20g fat/day. Isotope studies revealed that her jejunal bile acid content was normal and that her daily excretion of bile acids was higher than normal values. 1. Select the FALSE statement below: Following the ileal resection A. The post-operative diarrhea was secretory in origin B. The cholestyramine probably prevented the bile acids from inhibiting sodium and water absorption in the colon and prevented micelle formation C. The synthesis of bile acids probably increased D. The extraction of bile acids from the portal blood decreased E. The fecal fat resulted from some unabsorbed lipids
A. The additional bile in the feces post-operatively created an osmotic (not secretory) diarrhea, since the bile just pulled water (and solutes) that was already in the lumen...the bile did not pull water and solutes from the ECF (which happens with secretory diarrhea).
Intestinal slow waves (BER) A. Result from changes in the SIP syncytium B. Function to trigger action potentials and associated contractions in the muscle C. Are generated by enteric neurons D. Are found in the small intestine but not the large intestine E. Are depolarized by sympathetic stimulation
A. The slow waves are the resting membrane potential of the GI tract. It used to be thought they were generated by the Na/K ATPase activity, but it is now believed they are generated by the SIP syncytium (smooth muscle cells, interstitial cells of Cajal and platelet-derived growth factor).
Which secretions are almost entirely under neural control? A. Salivary B. Gastric C. Pancreatic D. Hepatic E. Duodenal
A. While all of the secretions mentioned have a neural component, only salivation is dependent on stimulation via the PNS (facial and glossopharyngeal nerves)
The migrating myoelectric complex: A. Consists of strong abdoral contraction during phase III B. Is triggered by ingestion of a meal C. Is triggered by intestinal bacteria D. Has the most contractile activity during phase I E. Helps keep bacteria out of the colon
A. While there are 3-4 phases of the MMC, the strongest, sequential contractions are during phase III, which is associated with the secretion of motilin into the blood. The MMC occurs during times of fasting and serves to sweep undigested chyme and bacteria into the colon.
During digestion of a meal, secretion of acid by the stomach is A. Inhibited by hormones released from the duodenal mucosa B. Stimulated by impulses carried in the celiac nerve C. Stimulated by somatostatin D. Stimulated by hormones released from the jejunal mucosa E. Inhibited by gastrin
A. B- incorrect-- the celiac nerve doesn't go to the stomach.C- incorrect--somatostatin inhibits parietal cell HCl.D- incorrect-- no jejunal hormones or peptides increase HCl.E- incorrect-- gastrin stimulates HCl by increasing the insertion of proton pumps into the lumenal membrane. When chyme (acidic) enters the duodenum, multiple hormones are released into the blood. While gastrin will act directly on the parietal cell to increase acid secretion, secretin and GIP will inhibit gastrin secretion (and thus modulate acid secretion), and GIP may also inhibit parietal cell acid directly.
Gastric parietal cells secrete A. Intrinsic factor B. Gastrin C. Pepsin D. Serectin E. Cholecystokinin
A. Parietal cells secrete hydrogen ions (for HCl) production and intrinsic factor. The intrinsic factor helps to protect vitamin B12 from pancreatic proteases.
Intestinal slow waves (BER) A. Result from changes in the SIP syncytium B. Function to trigger action potentials and associated contractions in the muscle C. Are generated by energetic neurons D. Are found in the small intestine but not the large intestine E. Are depolarized by sympathetic stimulation
A. The slow waves are the resting membrane potential of the GI tract. It used to be thought they were generated by the Na/K ATPase activity, but it is now believed they are generated by the SIP syncytium (smooth muscle cells, interstitial cells of Cajal and platelet-derived growth factor).
During swallowing A. The swallowing center in the medulla controls primary peristalsis B. The lower esophageal sphincter contracts C. Pressure in the lower esophageal sphincter fall immediately D. Smooth muscle is the first to contract when peristalsis starts in the skeletal portion of the esophagus E. Secondary peristalsis in the esophagus is initiated by the voluntary act of swallowing
A. The swallowing center in the medulla initiates primary peristalsis. If food becomes lodged in the esophagus, local stretch will engage the enteric nerves contributing to secondary esophageal peristalsis (and local secretion of mucus).
During digestion of a meal, secretion of acid by the stomach is A. Inhibited by hormones released from the duodenal mucosa B. Stimulated by impulses carried in the celiac nerve C. Stimulated by somatostatin D. Stimulated by hormones release from the jejunal mucosa E. Inhibited by gastrin
A. When chyme (acidic) enters the duodenum, multiple hormones are released into the blood. While gastrin will act directly on the parietal cell to increase acid secretion, secretin and GIP will inhibit gastrin secretion (and thus modulate acid secretion), and GIP may also inhibit parietal cell acid directly
After eating a large meal at the Tombs, a medical student was walking home, and noticed someone following him. He ran all the way home with the stranger trailing him. What is LEAST likely to have occurred during this time? A. A massive intestinal vasodilation B. An increase in norepinephrine binding GI tract C. A reduction in salivary acinar cell secretion D. An increase in gastric acid secretion E. An increase in pyloric sphincter tone
B.
Bile is synthesized in hepatocytes A. True B. False
B.
Bile recycling occurs throughout the small intestine A. True B. False
B.
Bile secretions make a good buffer A. True B. False
B.
Lipids (by themselves) are readily absorbed in the small intestine A. True B. False
B.
Only 50% of primary bile is conjugated with glycine or taurine A. True B. False
B.
Primary bile acids are synthesized from a cholesterol backbone and they are only hydrophilic A. True B. False
B.
The unstirred water layer results solely from laminar flow A. True B. False
B.
What duodenal hormone stimulates bile production, gallbladder contractions and opening of the Sphincter of Oddi? A. Secretin B. Cholecystokinin C. Gastrin D. Serotonin
B.
Which of the following would delay or diminish the absorption of proteins? A. Secretion of CCK B. pH of 3 in the duedenum and early jejunum C. Increase in the NA/K ATpase activity in the basolateral membranes of the enterocytes D. Stimulation of pepsin secretion E. Inhibition of somatostatin release
B. If the duodenum remains acidic, pancreatic enzymes have low catalytic activity and will not be effective until later in the jejunum
What happens if the gall bladder was removed?
Cholecystectomy is performed in response to acute or chronic cholecystitis (inflammation of the gallbladder, with or without stones). Complications after successful surgery are rare, but 5-40% of patients may develop postcholecystectomy syndrome, experiencing chronic GI distress and pain in the upper right abdomen. Up to 20% of patients can develop diarrhea (taking years to resolve). Why? Can be treated with cholestyramine.
Undigested carbohydrates in the lower GI tract A. Will cause secretory diarrhea B. Will slow gastric emptying C. Will not undergo fermentation by bacteria D. Will increase motility in that area E. Will increase gastrin release
D.
What actions will occur when chyme is present in the duodenum? A. Stimulation of intestinal mucis by gastrin B. Stimulation of hepatic bile production by secretin C. Stimulation of pancreatic enzyme secretion by gastrin D. Stimulation of intestinal buffer secretion by secretin E. Conversion of chymotrypsinogen to chymotrypsin by enterkinase
D.
What happens if the ileum was removed?
Lose the bile transporters in the terminal ileum, so there is little to no recycling. Bile secreted by the gallbladder and liver will be excreted in feces. When the Sphincter of Oddi closes, the bile in the ducts is "vacuumed" into the gallbladder and stored. Overall the liver has to produce much more bile, since there is no recycling. Although the increased sodium and water entering the colon will increase sodium (and water) reabsorption, overall, the increase in bile and motility will cause diarrhea. Cholestyramine sequesters and binds the bile in an insoluble complex that reduces the osmotic effects.
What are the effects of gall bladder removal on GI function?
No serious effects! Liver will just keep producing bile during digestion...overall it will produce more than normal because there is no storage. When the Sphincter of Oddi closes (when chyme is out of the duodenum) the recycled bile stays in the bile ducts. Patients can have diarrhea, but usually not much of a problem.
