Gastrointestinal Physiology Flashcards
Endocrine secretions of the intestine
GIP
CCK
Secretin
Gastrin
Glucagon-Like Peptide (GLP)
Then enteric nervous system, endocrine cells, paracrine cells and local tissue factors are examples of ___________ control of the GI tract.
Then enteric nervous system, endocrine cells, paracrine cells and local tissue factors are examples of Intrinisic control of the GI tract.
Factors that increase blood flow to the GI tract
NO
PSNS Stimulation
_________ acts on muscarinic receptors, inhibits Somatostatin and promotes histamine and gastrin.
AcH acts on muscarinic receptors, inhibits Somatostatin and promotes histamine and gastrin.
___________ of the GI tract spontaneously depolarizes and repolarizes
Visceral Smooth Muscle of the GI tract spontaneously depolarizes and repolarizes
GI: __________: increases the reabsorption of Na+ and increases the secretion of K+, is NOT vasoactive.
Aldosterone: increases the reabsorption of Na+ and increases the secretion of K+, is NOT vasoactive.
__________
Increases peptic cell secretion
Contraction of LES and pyloric spincter
Increase gastric motility and blood flow
Gastrin
_____________ are necessary for digestion.
Hydrolytic Enzymes are necessary for digestion.
_________ drugs block histamine receptors
-tidine drugs block histamine receptors
In dogs and cats, the pancreas produces ________, which is unlike many other species.
In dogs and cats, the pancreas produces GIF, which is unlike many other species.
__________ use water to break bonds
Hydrolytic Enzymes use water to break bonds
Peristalsis
Movement in the aborad direction
Perfusion of the GI tract is controlled by :
Autonomic Nervous System
Endocrine Secretion
Paracrine Secretion
Local Tissue Factors
HCO3 production is (increased/decreased) by prostaglandins
HCO3 production is (increased/decreased) by prostaglandins
Preganglionic neurons of the _________ nervous system origniate from the vagus or pelvic nerves to have effect on the GI tract.
Preganglionic neurons of the parasympathetic nervous system origniate from the vagus or pelvic nerves to have effect on the GI tract.
__________: increased secretion of HCO3 into the lumen and H into the plasma.
Acid Tide: increased secretion of HCO3 into the lumen and H into the plasma.
_____________ of the heart allow the action potential to travel the fastest due to the least resistance.
Perkinje Fibers of the heart allow the action potential to travel the fastest due to the least resistance.
Local tissue factors have a ___________ effect on the blood vessels of the Gi tract
Local tissue factors have a vasodilatory effect on the blood vessels of the Gi tract
__________ nervous system neurons originates from the craniosacral plexus.
Parasympathetic nervous system neurons originates from the craniosacral plexus.
________ is only secreated by the salivary glands and follicular cells of the thyroid glands.
Iodide is only secreated by the salivary glands and follicular cells of the thyroid glands.
__________ secretions of the intestine increase secretion by stimulating crypt cells and are vasodilatory
Paracrine secretions of the intestine increase secretion by stimulating crypt cells and are vasodilatory
_____________________
Histamine and Prostaglandin
Types of Intestinal secretions
Exocrine
Paracrine
Endocrine
Antiperistalsis is a prominant feature in what species
Equine
______________________
Feature at the pelvic flexure to allow for increased fermentation time
___________: paracrine secretion that increases GI motility.
Serotonin: paracrine secretion that increases GI motility.
Ruminants use salivary glands as
Ruminants use salivary glands as a source of ruminal and reticular fluid
_______________________
Essential to buffer acid produced by fermentation
GI cells throughout their lifetime move from ________ to ___________
GI cells throughout their lifetime move from crypt to villi
The __________ of the GI tract is largely reabsorptive, especially to Cl and Na.
The Large Intestine of the GI tract is largely reabsorptive, especially to Cl and Na.
Describe how protein is broken down for absorption
Protein broken down to oligopeptides by protease
Oligopeptides broken down to amino acids by brush border oligopeptidases
___________- blood leaving the stomach is markedly alkaline.
Alkaline Tide- blood leaving the stomach is markedly alkaline.
________ and _________ are transported from the pancreas for digestion together.
Amylase and Protease are transported from the pancreas for digestion together.
____________: Stimulates gastrin secretion and promotes closrue of the pyloric sphincter with CCK.
Gastrin: Stimulates gastrin secretion and promotes closrue of the pyloric sphincter with CCK.
________ and _______ are products of the parasympathetic nervous system that aid in the perfusion of the GI tract.
VIP and NO are products of the parasympathetic nervous system that aid in the perfusion of the GI tract.
Dogs and cats use salivary glands for __________.
Dogs and cats use salivary glands for evaporative cooling.
The composition of saliva is similar to plasma, with the exceptions of
Increased PO4 in ruminant saliva
Increased [I]
ACH bound to muscarinic receptors promotes the secretion of _______ from the epithelium.
ACH bound to muscarinic receptors promotes the secretion of NO from the epithelium.
_________ blocks all muscarinc receptors
Atropine blocks all muscarinc receptors
________ nervous system neurons originates from the thoracolumbar plexus
Sympathetic nervous system neurons originates from the thoracolumbar plexus
_______ control of the GI is achieved through the regulation of perfusion.
Indirect control of the GI is achieved through the regulation of perfusion.
_________: from the SNS vasoconstricts and decreases blood flow of the GI tract.
Norepinephrine: from the SNS vasoconstricts and decreases blood flow of the GI tract.
__________ cells of the GI tract are acid inhibiting by inhibiting gastrin.
D cells of the GI tract are acid inhibiting by inhibiting gastrin.
____________: stimulated by acidic luminal pH.
Stimulates bile and pancreatic secretion and crypt cell secretion
Inhibits gastric secretion, gastric motility and gastric emptying
Secretin: stimulated by acidic luminal pH.
Stimulates bile and pancreatic secretion and crypt cell secretion
Inhibits gastric secretion, gastric motility and gastric emptying
Antiperistalsis
Movement in the orad direction
___________ of the heart generates the action potential.
SA Node of the heart generates the action potential.
Peristalsis occurs in what part of the stomach
Antrum
The GI tract can receive up to ______% of cardiac output.
The GI tract can receive up to 30% of cardiac output.
Proton moves into the GI lumen by way of _________ in the Gastric Parietal Cells.
Proton moves into the GI lumen by way of H-K ATPase in the Gastric Parietal Cells.
________________
Increased pancreatic enzyme
Increased pancreatic cell death
Inflammation
Pancreatitis
Side effect of -prazole drugs
H+ is sequestered inside the cell which leads to increased pH in the lumen. Can lead to bacterial overgrowth
Example of plant beta-polymer carbohydrates
Cellulose
Water enters the lumen by osmosis, it follows _________ secretion.
Water enters the lumen by osmosis, it follows Cl- secretion.
Interstitial cells of the GI tract differ from cardiac pacemaker cells in that
Interstitial cells of the GI tract differ from cardiac pacemaker cells in that interstital cells dont depolarize all the way to threshold
____________
Produced by the glandular stomach
Stimulate release of Growth Hormone
Appetite promoting
Peaks right before a meal
Promote food intake by decreasing sensitivity to distention receptors
Ghrelin
Transporters on the Parietal Cells of the GI tract
H-K ATPase
HCO3-Cl Exchanger
Cl Channel
K Channel
Describe the negative feedback mechanism on D cells of the GI tract
Increased lumen [H+] stimulates D cells
Increased ACH due to the PSNS inhibits D cells
____________ reflex is initiated by gastric dilation and its effect is peristaltic and mas movement at the distal colon (entry of feces into the rectum)
Gastrocolic reflex is initiated by gastric dilation and its effect is peristaltic and mas movement at the distal colon (entry of feces into the rectum)
_________ nervous system acts as a pre-synaptic inhibitor of GI tract motility
Sympathetic nervous system acts as a pre-synaptic inhibitor of GI tract motility
The gastrointestinal tract has a protective function due to ____________.
The gastrointestinal tract has a protective function due to immunocytes.
The exocrine glands make tubular fluid alkaline by reabsorbing __________ and secreting _________.
The exocrine glands make tubular fluid alkaline by reabsorbing Cl- and secreting HCO3-.
Phases of Gastric Motility
Cephalic Phase
Gastric Phase
Intestinal Phase
____________ secretes the majority of hydrolytic enzymes.
Pancreas secretes the majority of hydrolytic enzymes.
Filtration and flow through the kidney is voluntary/involuntary.
Filtration and flow through the kidney is voluntary/involuntary.
___________
“Inhibitory”
@Stomach: inhibits histamine secreting cells
Somatostatin
_________ secretion: enters the lumen of the tubular gut at the mouth or small intestine- more alkaline
Secondary secretion: enters the lumen of the tubular gut at the mouth or small intestine- more alkaline
Regulation of GI function is largely under __________ control.
Regulation of GI function is largely under CNS control.
T/F: Carbohydrates, Protein and Lipids can be absorbed in the form ingested.
False
______________________
They must be digested in order to be absorbed
_____ cells of the GI tract are acid promoting.
ECL cells of the GI tract are acid promoting.
__________ functions to emulsify lipid. Separates lipid into small pieces to increase surface area and keeps the pieces from going back together.
Bile functions to emulsify lipid. Separates lipid into small pieces to increase surface area and keeps the pieces from going back together.
After _________ flow through the gastrointestinal tract becomes involuntary.
After swallowing flow through the gastrointestinal tract becomes involuntary.
Describe how carbohydrate is broken down for absorption
Starch/Glycogen broken down to Maltose (and other products) by amylase
Amylase products are broken down into transportable forms by brush border enzymes
VIP and AcH in the GI tract promote the production of ________.
VIP and AcH in the GI tract promote the production of NO.
Inhibitory motor neurons of the GI tract secrete ______, ______ and __________ to cause relaxation.
Inhibitory motor neurons of the GI tract secrete NO, VIP and ATP to cause relaxation.
Electrolytes that can always be found in the GI lumen
Cl, K, Na and Water
H-K ATPase only found in
Gastric Parietal Cells
Alpha Intercalated Cells
_________ drugs inhibit H-K ATPase transporters
-prazole drugs inhibit H-K ATPase transporters
CO2, H+ and K+ are examples of
Local Tissue Factors
Carbohydrates can be absorbed in ________ and __________ forms.
Carbohydrates can be absorbed in alpha-polymer and beta-polymer forms.
________ stimulates skeletal muscle to contract.
AcH stimulates skeletal muscle to contract.
___________ plays an important role in overall control of insulin relased by beta cells of the pancreas.
Gastric Inhibitory Peptide (GIP) plays an important role in overall control of insulin relased by beta cells of the pancreas.
There is a significant increase in luminal __________ ports in the colon.
There is a significant increase in luminal Na uniports ports in the colon.
_________ control mechanisms are initiated outside of the GI tract.
Extrinsic control mechanisms are initiated outside of the GI tract.
_____________
@ SI: inhibits CCK and Secretin
Slows nutrient absorption
Somatostatin
Secretion of amylase begins when
Before ingesta reaches the small intestine
______ and _______ cells of the stomach can be pharmacologically altered.
Parietal and Mucous cells of the stomach can be pharmacologically altered.
Paracrine secretions of the intestine
Histamine
Prostaglandins
Examples of sources of plant alpha-polymer carbohydrates
Amylase
Amylopectin
Hormone productionis greatest in what sections of the GI tract
Glandular Stomach
Small Intestine
_____________: stimulated by glucose, monoacylglycerols and fatty acids; promotes the release of insulin.
GIP: stimulated by glucose, monoacylglycerols and fatty acids; promotes the release of insulin.
GI motility occurs without outside stimulation in response to ________.
GI motility occurs without outside stimulation in response to Stretch.
Salivary gland, liver and pancrease secrete ________ secretion.
Salivary gland, liver and pancrease secrete aqueous secretion.
___________ increase uptake of Cl from the basolateral membrane and increase the number of open Cl ports in the luminal membrane.
Secretagogues increase uptake of Cl from the basolateral membrane and increase the number of open Cl ports in the luminal membrane.
__________ inhibits gastrin
Somatostatin inhibits gastrin
Excitatory motor neurons can be stimulated in the GI tract by
GI itself
CNS
Cl- enters the basolateral membrane of GI cells by
Na-K-2Cl Symport
Na-Cl Symport
HCO3- Cl Exchanger
Pancreatic disease is assessed through evaluation of ______________.
Pancreatic disease is assessed through evaluation of Plasma [Pancreatic Enzyme].
______________________
Pancreatic Lipase Immunoreactivity (PLI)
Trypsin-Like Immunoreactivity (TLI)
Bile increases the surface area of lipid in order for ___________ to have better access.
Bile increases the surface area of lipid in order for Pancreatic Lipases to have better access.
___________ nervous system exerts its effect in a particular area of the GI tract.
Parasympathetic nervous system exerts its effect in a particular area of the GI tract.
Describe the process of GI motility when stimulated by the CNS
Preganglionic neurons from the brain secrete ACH onto nicotinc receptors of the motor neurons
Excitatory motor neurons secrete their products and cause contraction of circular smooth muscle
Inhibitory motor neurons secrete their products and cause relaxation of circular smooth muscle
GI:__________: increases the absorption of calcium, phorphorus and magnesium
Calcitriol: increases the absorption of calcium, phorphorus and magnesium
-_________ drugs increase insulin by inhibiting the enzyme (DPP4) that decrades incretins
-gliptin drugs increase insulin by inhibiting the enzyme (DPP4) that decrades incretins
Paracrine secretions typically have a __________ effect on the blood vessels of the GI tract.
Paracrine secretions typically have a vasodilatory effect on the blood vessels of the GI tract.
_____________ - thin layer of alkaline fluid in the glandular stomach, created by mucin trapping HCO3
Gastric Mucosal Barrier - thin layer of alkaline fluid in the glandular stomach, created by mucin trapping HCO3
Important pancreatic proteases
Trypsinogen
Chymotrypsinogen
Procarboxypeptidase
________ glands have an effect on the GI tract but are located outside the gut wall.
Exocrine glands have an effect on the GI tract but are located outside the gut wall.
Exocrine secretions of the small intestine
Mucin
Guanylin
Enterokinase
As cells of the GI tract get older they transition from net __________ to net __________ in function.
As cells of the GI tract get older they transition from net secretory to net absorptive in function.
Antagonists of HCl production
Somatostatin
Prostaglandins
Secretin
CCK
___________ competitively inhibits gastrin by binding to its receptors.
CCK competitively inhibits gastrin by binding to its receptors.
Bacteria have developed toxins to stimulate the release of _________ in the GI tract.
Bacteria have developed toxins to stimulate the release of guanylin in the GI tract.
_______________ when in decreased concentration in the GI tract stimulate production of AGII and ADH.
Effective Circulating Hormone (ECH) when in decreased concentration in the GI tract stimulate production of AGII and ADH.
Efferent Neurons are related to _______ responses.
Efferent Neurons are related to motor responses.
HCO3 production is (increased/decreased) by the SNS
HCO3 production is (increased/decreased) by the SNS
___________ control are mechanisms found entirely within the GI tract.
Intrinsic control are mechanisms found entirely within the GI tract.
________ phase of gastric motility is characterized by being stimulated by sight, smell and taste, distention of the esophagus and hypoglycemia. The vasovagal reflex stimulates parietal, peptic and mucosal cells.
Cephalic phase of gastric motility is characterized by being stimulated by sight, smell and taste, distention of the esophagus and hypoglycemia. The vasovagal reflex stimulates parietal, peptic and mucosal cells.
________ cells respond directly to contents of the GI lumen.
Endocrine cells respond directly to contents of the GI lumen.
___________: secreted by crypt cells of the intestine, binds luminal membrane receptors to increas secretion.
Guanylin: secreted by crypt cells of the intestine, binds luminal membrane receptors to increas secretion.
____________: stimulated by fatty acids, monoacylglycerols.
Stimulates contraction of the gallbladder, pancreatic acinar secretion, crypt cell secretion, bile duct secretion and decreases gastric emptying.
Inhibits gastric motility and HCl secretion.
CCK: stimulated by fatty acids, monoacylglycerols.
Stimulates contraction of the gallbladder, pancreatic acinar secretion, crypt cell secretion, bile duct secretion and decreases gastric emptying.
Inhibits gastric motility and HCl secretion.
Pacemaker cells spontaneously depolarize by
Pacemaker cells spontaneously depolarize by closing K+ channels
___________ reflex is initiated by the CNS and its effect is via the SNS and PSNS to the GI tract.
Vasovagal reflex is initiated by the CNS and its effect is via the SNS and PSNS to the GI tract.
___________ is essential for maturation of red blood cells
Vitamin B12 is essential for maturation of red blood cells
The most abundant carbohydrate polymer is ___________.
The most abundant carbohydrate polymer is cellulose.
PSNS: Preganglionic Neuron secretes _______ onto a __________ receptor. The postganglionic neuron secretes _________ onto a __________ receptor causing ___________.
PSNS: Preganglionic Neuron secretes ACH onto a Nicotinic receptor. The postganglionic neuron secretes ACH onto a Muscarinic receptor causing dilation.
Digestion requires the __________ and __________.
Digestion requires the Small Intestine and Pancreas.
SNS: Preganglionic Neuron secretes _______ onto a __________ receptor. The postganglionic neuron secretes _________ onto a __________ receptor causing ___________.
SNS: Preganglionic Neuron secretes ACH onto a nicotinic receptor. The postganglionic neuron secretes NE onto a alpha-1 adrenergic receptor causing constriction.
_____________________
NE also binds to beta-2 adrenergic receptors to cause dilation
Exocrine glands of the gastrointestinal tract include
Salivary glands
Pancreas
Liver
_________ of the heart reaches threshold the fastest
AV Node of the heart reaches threshold the fastest
Endocrine secretions of the GI tract
Epinephrine
Peptide hormones
Effective Circulating Hormone (ECH)
D cells of the GI tract have receptors for
ACH
_____________
@Pancreas: inhibits exocrine secretion and secretion of glucagon by alpha-cells
Inhibit insulin secretion by beta cells
Somatostatin
GI: ___________: (SNS) increases absorption and reabsorption of electrolytes (and water)
Epinephrine: (SNS) increases absorption and reabsorption of electrolytes (and water)
________ nervous system promotes gastric motility
Parasympathetic nervous system promotes gastric motility
_______ cells of the GI tract are gastrin promoting.
G cells of the GI tract are gastrin promoting.
Filtration through the kidney is regulated by
Blood Pressure
Neurotransmitter
Hormones
There is an increased number of gastric parietal cells in the _______ of the stomach.
There is an increased number of gastric parietal cells in the Corpus of the stomach.
Cl- in the GI tract drives the secretion of
Na, K and H
ECL cells secrete _________.
ECL cells secrete histamine.
Flow of water (increases/decreases) from duodenum to large intestine.
Flow of water (increases/decreases) from duodenum to large intestine.
___________ causes skeletal muscle to relax.
Lack of AcH causes skeletal muscle to relax.
D Cells in the antrum of the stomach have receptors for
CCK
ACH
_________ control is the direct interaction of a NT, Hormone, or Paracrine secretion with parts of the GI tract.
Direct control is the direct interaction of a NT, Hormone, or Paracrine secretion with parts of the GI tract.
Incretins
Substances that stimulate the beta cells of the pancreas to secrete insulin
__________: from the adrenal medulla has vasoconstrictive and vasodilatory effects in the GI tract.
Epinephrine: from the adrenal medulla has vasoconstrictive and vasodilatory effects in the GI tract.
The form in which lipid is absorbed is ____________.
The form in which lipid is absorbed is Triacylglycerol.
_____________ drugs inhibit prostaglandin production.
COX inhibitors and Glucocorticoids drugs inhibit prostaglandin production.
____________
Increased eating
Increased amount of feces
Undigested lipid in form of fat in feces
Decreased weight
Pancreatic insufficiency
____________ of the GI Interstitial cells allows less stimulus to reach threshold.
“Priming” of the GI Interstitial cells allows less stimulus to reach threshold.
Bile is stored in the __________
Bile is stored in the gallbladder
________________
Exception: Equine! They don’t have a gallbladder
Acid is produced in what parts of the stomach
Fundus and Corpus
____________: products of metabolism that affect the behavior of blood vessels.
Local Tissue Factors: products of metabolism that affect the behavior of blood vessels.
__________ function is dilute and buffer chyme to create optimum pH; also hydrolyzes protein, carbohydrate, lipid and nucleic acids.
Exocrine Pancreas function is dilute and buffer chyme to create optimum pH; also hydrolyzes protein, carbohydrate, lipid and nucleic acids.
_________ is an important source of nitrogen for microbes of the forestomach of ruminants.
Urea is an important source of nitrogen for microbes of the forestomach of ruminants.
The products of amylase stimulate _______ and _________.
The products of amylase stimulate secretion and blood flow.
D cells of the GI tract secrete _________.
D cells of the GI tract secrete Somatostatin.
Factors the decrease blood flow to the GI tract
ADH
E
NE
AGII
SNS Stimulation
Visceral smooth muscle is different from skeletal muscle because it is stimulated to
Visceral smooth muscle is different from skeletal muscle because it is stimulated to contract AND relax
__________ from the liver, break down fat by physical digestion.
Bile Acids from the liver, break down fat by physical digestion.
The _______ phase is inhibitory; Secretin, CCK and Gastrin are released.
The Intestinal phase is inhibitory; Secretin, CCK and Gastrin are released.
_________ occurs when a cell secretes a product that has an effect on a neighboring cell.
Paracrine secretion occurs when a cell secretes a product that has an effect on a neighboring cell.
_____________
Vasodilatory
Increases gastric motility
Histamine
___________ of the GI tract is a major site of absorption.
Small Intestine of the GI tract is a major site of absorption.
Salivary glands are stimulated by
Neurotransmitters
Hormone Secretions
Paracrine Secretions
Peptide hormones from the GI tract have a ___________ effect.
Peptide hormones from the GI tract have a vasodilatory effect.
________ and ________ are responsible for the absorption of lipids.
Bile and Pancreatic Proteases are responsible for the absorption of lipids.
_________ cell of the GI tract produces break down substances.
Peptic (Chief) cell of the GI tract produces break down substances.
_________ secretion: progress toward the lumen of the tubular gut, they are modified by secretory and reabsorptive actvities of ductular cells.
Primary secretion: progress toward the lumen of the tubular gut, they are modified by secretory and reabsorptive actvities of ductular cells.
________ cells of the glandular stomach produce mucin and HCO3
Mucus (Neck) cells of the glandular stomach produce mucin and HCO3
Afferent Neurons are related to ___________ responses.
Afferent Neurons are related to sensory responses.
_____________: stimulated by food breakdown products to stimulate the release of insulin.
Glucagon-Like Peptide (GLP): stimulated by food breakdown products to stimulate the release of insulin.
__________ reflex is initiated by distention of the ileum and its effect is to decrease gastric motility.
Iliogastric reflex is initiated by distention of the ileum and its effect is to decrease gastric motility.
______ and _______ are incretins of the GI tract
GIP and GLP-1 are incretins of the GI tract
___________ cells of the GI tract produce HCl and GIF
Parietal cells of the GI tract produce HCl and GIF
Cells in the gastric pit
Mucin (Neck) Cells
Gastric Parietal Cells
_________ nervous system inhibits (slows) GI motility
Sympathetic nervous system inhibits (slows) GI motility
___________ nervous system causes vasodilation in areas where food is present.
Parasympathetic nervous system causes vasodilation in areas where food is present.
Veterinarians request that no food be fed to patients before surgery, this is because:
Anesthesia causes a loss of CNS control
Food in the gut increases the perfusion
___________ are considered the pacemaker cells of the GI tract.
Interstitial Cells are considered the pacemaker cells of the GI tract.
_________ nervous system exerts its effect everywhere by stimulating the secretion of epinephrine.
Sympathetic nervous system exerts its effect everywhere by stimulating the secretion of epinephrine.
Agonist of HCl secretion
AcH
The ________ does not secrete hydrolytic enzymes.
The liver does not secrete hydrolytic enzymes.
ECL cells of the GI tract have receptors for
ACH
CCK
Somatostatin
The goal of the exocrine glands is to make the fluid entering the gut __________.
The goal of the exocrine glands is to make the fluid entering the gut alkaline.
Cells of the GI tract live for _________
Cells of the GI tract live for 2-4 days
____________________
This was a question of the Blue final***
G cells of the GI tract have receptors for
GRP
Somatostatin
Pacemaker cells of the Heart
SA Node
AV Node
Bundle of His
Perkinje Fibers
Distention of the stomach (initiating the vasovagal reflex) and the presence of peptides and amino acids in the lumen stimulate the __________ phase.
Distention of the stomach (initiating the vasovagal reflex) and the presence of peptides and amino acids in the lumen stimulate the gastric phase.
Na and K move into the GI lumen _________
Na and K move into the GI lumen paracellularly
_____________: secreted by absorptive cells to convert trypsinogen to active trypsin
Enterokinase: secreted by absorptive cells to convert trypsinogen to active trypsin
Secretion of the pancreas is stimulated by
Sensory (Sight, taste)
Vasovagal Reflex (distention)
AcH (NT)
Gastrin
CCK
Secretin
The sympathetic nervous system displays direct inhibition of GI tract motility at the ___________.
The sympathetic nervous system displays direct inhibition of GI tract motility at the sphincters.
Absorption in the GI tract would not occur without the secreation of ________ first.
Absorption in the GI tract would not occur without the secreation of water first.
_____________ is produced by the glandular stomach, it binds to vitamin B12 to protect it from digestion.
Gastric Intrinsic Factor (GIF) is produced by the glandular stomach, it binds to vitamin B12 to protect it from digestion.
EC cells and Serotonin secreting cells are important ___________ cells of the GI tract.
EC cells and Serotonin secreting cells are important paracrine cells of the GI tract.
Leakiness of tight junctions (increases/decreases) from duodenum to large intestine.
Leakiness of tight junctions (increases/decreases) from duodenum to large intestine.
Post ganglionic neurons of the _______ nervous system inhibit postganglionic neurons of the _________ nervous system.
Post ganglionic neurons of the sympathetic nervous system inhibit postganglionic neurons of the parasympathetic nervous system.
_________: secreted by goblet cells of the intestine; initiated by increased [H+], hyperosmolarity and stretch.
Mucin: secreted by goblet cells of the intestine; initiated by increased [H+], hyperosmolarity and stretch.
Excitatory neurons of the GI tract secrete ________ and ___________ to cause contraction.
Excitatory neurons of the GI tract secrete ACH and Substance P to cause contraction.
Contraction of circular longitundinal muscle (increases/decreases) the diameter of the lumen.
Contraction of circular longitundinal muscle (increases/decreases) the diameter of the lumen.
___________________
Think, Chinese finger trap
Describe the process of GI motility when stimulated by the GI itself
EC cells are stimulated to secrete serotonin by GI stimulation
Serotonin stimulates the sensory neuron
Sensory neuron stimulates myenteric and submucosal plexus
Excitatory and inhibitory motor neurons are stimulated to release their products
Contraction of circular smooth muscle occurs in the oral direction
Relaxation of circular smooth muscle occurs in the anal direction
________: in the GI tract inhibits actin-myosin interaction in muscle.
VIP: in the GI tract inhibits actin-myosin interaction in muscle.
Examples of source of animal alpha-polymer carbohydrates
Glycogen
_______________
Decreased pancreatic enzymes due to a decrease in number of pancreatic cells.
Can lead to decreased insulin if immune mediated diabetes is triggered.
Can also lead to anemia due to decreased production of GIF.
Exocrine Pancreatic Insufficiency