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GI - Pt 3 Secretions Flashcards

1
Q

Serous (acinar) cells secrete [] & []

Mucus acinar cell secrete []

A

Serous (acinar) cells secrete water & bicarb

Mucus acinar cell secrete mucus

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2
Q

Salivary Secretions:

  • Almost totally under [] NS control
    • Primarily []
    • Secondarily []
  • What are the ~4 main secretions we covered?
A
  • Almost totally under Autonomic NS control
    • Primarily parasympathetic
    • Secondarily sympathetic
  • What are the ~4 main secretions we covered?
    • Salivary Amylase
    • Lingual lipase
    • Haptocorrin
    • Intrinsic Factor
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3
Q

Salivary Amylase:

  • Indentical to [] amylase
  • Its optimum resides around pH - []
  • Cleaves the interal [] [] [] []
A
  • Indentical to pancreatic amylase
  • Its optimum resides around pH - 7
  • Cleaves the interal alpha 1-4 glycosidic bonds
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4
Q

Lingual Lipase

  • secreted by the glands of the []
  • Begins digestion of []
  • Optimal pH resides around - [] []
A
  • secreted by the glands of the tongue
  • Begins digestion of triglycerides
  • Optimal pH resides around - acidic conditions
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5
Q

Haptocorrin

  • It is a []
  • Binds vitamin [] in the []/duodenum
    • so it protects B12 in [] environments.
  • VERY similar to [] []
    • This protects B12 in the []
A

Haptocorrin

  • It is a glycoprotein
  • Binds vitamin B12 in the stomach/duodenum
    • so it protects B12 in acidic environments.
  • VERY similar to Instrinsic Factor
    • This protects B12 in the intestines
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6
Q

Lubrication & protection salivary secretions:

  • [] - protect stomach from initial [] stress
  • [] aspect (bacteriocidal)
  • [] (IgA) - optimizing an immunological response against bacteria and virus
  • [] - chelates Iron
A
  • Mucus - protect stomach from initial food stress
  • Lyzozymal aspect (bacteriocidal)
  • Immunoglobin A (IgA) - optimizing an immunological response against bacteria and virus
  • Lactoferrin - chelates Iron
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7
Q

Dry Mouth

  • [] refers to chronic infectins of the buccal mucosa
    • Dissolution of [] components by [] acids produced by enzymatic actions of masses of []
A
  • Xerostomia refers to chronic infectins of the buccal mucosa
    • Dissolution of inorganic components by organic acids produced by enzymatic actions of masses of microorganism
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8
Q

Parotid Gland

  1. Largest [] gland
  2. Made of serous cells with produce []/[] and []
  3. At rest, produce [] of saliva volume
  4. Active, produces [] of saliva volume
A
  1. Largest salivary gland
  2. Made of serous cells with produce H2O/HCO3- and enzymes
  3. At rest, produce 25% of saliva volume
  4. Active, produces 80% of saliva volume
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9
Q

Submandibular Gland

  1. Unstimulated, accounts for [] of overall saliva volume
  2. It is a [] salivary gland
    1. [] is the major component
    2. Also has a [] component.
A
  1. Unstimulated, accounts for 70% of overall saliva volume
  2. It is a mixed salivary gland
    1. mucus is the major component
    2. Also has a serous component.
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10
Q

Sublingual Gland

  1. Mainly a [] gland
    1. contains a very minor [] portion
A
  1. Mainly a mucus gland
    1. contains a very minor serous portion
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11
Q

T/F

Saliva secreted by serous/mucus acinus is modified in the intercalated duct and not the striated duct?

A

FALSE

The modification of saliva happens in the stiated duct

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12
Q
  • Salivary glands receive a high blood flow which results in the production of a large volume of []
A

fluid

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13
Q
  • Salivary glands receive both [] and [] innervation
    • Parasympathetic is the [] component and is done by 2 nerves:
      • [] Nerve (VII)
      • [] (IX)
    • Sympathetic is the []component done through the [] spinal cord via the superior [] ganglion
A
  • Salivary glands receive both parasympathetic and sympathetic innervation
    • Parasympathetic is the major component and is done by 2 nerves:
      • Facial Nerve (VII)
      • Glossopharyngeal Nerve (IX)
    • Sympathetic is the minor component done through the thoracic spinal cord via the superior cervical ganglion
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14
Q

For salivary glands, even though they receive Para/Symp innervation, [] innervation is more important because they are somehow [] to the salivary glands. So, if this innervation is cut off…the glands would []

A

For salivary glands, even though they receive Para/Symp innervation, parasympathetic innervation is more important because they are somehow nutritive to the salivary glands. So, if this innervation is cut off…the glands would “die”

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15
Q

Salivary glands, Autonomics regulate…

  1. secretions by acting on [] cells
  2. Blood flow by acting on [] networks
  3. Growth by acting directly on [] cells
A
  1. secretions by acting on myoepithelial cells
  2. Blood flow by acting on arteriolar networks
  3. Growth by acting directly on acinar cells
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16
Q

Parasympathetic flow of Salivary glands

  • Receptors - [] and []
  • [] of transport process
  • Contraction of [] cells
  • [] the blood vessels
  • [] the cellular activity resulting in [] of the cell.
A
  • Receptors - muscarinic and cholinergic
  • Activation of transport process
  • Contraction of myoepithelial cells
  • Vasodilate the blood vessels
  • Increase the cellular activity resulting in growth of the cell.
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17
Q

Sympathetic (w/ Para)

  • Uses [] receptors
  • Increases secretion, metabolism, and growht
  • With [] parasympathetic stimulation..
    • produces a more[] secretion
    • increases []
    • Causes [] - reduced [] secretions.
A
  • Uses B2 adrenergic receptors
  • Increases secretion, metabolism, and growth
  • With reduced parasympathetic stimulation..
    • produces a more viscous secretion (thicker), = nervous
    • increases mucus
    • Causes vasoconstriction - reduced serous secretions.
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18
Q

Salivary Flow

  1. [] [] [] (VIP), a [], is released at the [] end and mediates []
A

Vasoactive intestinal peptide (VIP), a neurocrine, is released at the postganglionic end and mediates vasodilation

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19
Q
  • Conditioned reflex like smell/taste –>
  • stimuli in the [] [] in the medulla Oblongata –>
  • Parasymp Nerves: [] (VII) & –> releases [] & [] –>
  • [] and Sailvary gland stimulation –>
  • In salivary gland: Increase in [] = Increase in [] –> Increase in metabolism, secretion, growth, myoepithelial contraction.
A
  • Conditioned reflex like smell/taste –>
  • stimuli in the Nucleii Salvatorii in the medulla Oblongata –>
  • Parasymp Nerves: Facial (VII) & Glossopharyngeal (IX) –> releases ACh & VIP –>
  • Vasodilation and Salivary gland stimulation –>
  • In salivary gland: Increase in IP3 = Increase in Ca2+ –> Increase in metabolism, secretion, growth, myoepithelial contraction.
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20
Q
  • Conditioned reflex like smell/taste –>
  • Sympathetic nerves T1/T2/T3 - release [] –>
  • Superior [] ganglion–> postgonglionic axons release [] at salivary gland that bind to [] [] receptors –> increase in [] = increase in [] –> increaes metabolism, cell contraction, secretion, growth.
A
  • Conditioned reflex like smell/taste –>
  • Sympathetic nerves T1/T2/T3 - release ACh –>
  • Superior Cervical ganglion–> postgonglionic axons release norepinephrine at salivary gland that bind to B2 adrenergic receptors –> increase in cAMP = increase in Ca2+ –> increaes metabolism, cell contraction, secretion, growth.
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21
Q

Saliva Compostion:

  • High [] concentration
  • Low []
  • Inorganic Composition:
    • K+ is always [] than plasma
    • Na+ is [] than plasma
    • CL- is [] than plasma
    • HCO3- is [] than plama (except at [] [])
A
  • High K+ concentration
  • Low Osmolarity
  • Inorganic Composition:
    • K+ is always greater than plasma
    • Na+ is less than plasma
    • CL- is less than plasma
    • HCO3- is greater than plama (except at low flow)
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22
Q

All ions in salivary acinus = the plasma [] of ions

A

concentration

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23
Q

T/F - all ion in the acinus are in equal concentration to the ionic concentration of the plasma

A

True

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24
Q

Striated Ductal Function

  • Reabsorb [] and []
  • Secrete [] and []
  • [] dependent
  • More [] and [] leaves than [] and [] enter
  • Epithelium is relatively [] to H2O
  • As saliva leaves the duct, it is []
A
  • Reabsorb Na+ and Cl-
  • Secrete K+ and HCO3-
  • Time dependent
  • More Na+ and Cl- leaves than K+ and HCO3- enter
  • Epithelium is relatively impermeable ot H2O
  • As saliva leaves the duct, it is hypotonic
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25
Q

As flow past the salivary duct cells increase, the time for resorptive and secretory processes []; saliva moves toward []

A

As flow past the salivary duct cells increase, the time for resorptive and secretory processes decreases; saliva moves toward isotonicity

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26
Q

As salivary flow rate increase:

  • Na+ and Cl- concentrations in the lumen []
  • [K+] in the lumen [] slightly
  • [HCO3-] in the lumen [] because its secretion is increased by the same [] that increase flow rate.
A
  • Na+ and Cl- concentrations in the lumen increase
  • [K+] in the lumen decreases slightly
  • [HCO3-] in the lumen increases because its secretion is increased by the same stimuli that increase flow rate.
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27
Q

Even when salivary flow rate increase, Na+ and Cl- will [] reach their concentrations in the plasma.

A

Even when salivary flow rate increase, Na+ and Cl- will never reach their concentrations in the plasma.

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28
Q
  • Increased Flow rate –> Increased metabolism and Increased[] and [] production —> H+ and [] production
  • The H+ gets [], but the HCO3- does not…so pH of saliva will [].
A
  • Increased Flow rate –> Increased metabolism and Increased CO2 and H2O production —> H+ and HCO3- production
  • The H+ gets buffered, but the HCO3- does not…so pH of saliva will increase.
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29
Q

2 functions of Esophageal mucus secretions:

A

Lubrication

protection against gastric reflux

30
Q

Intrinsic factor is secreted by [] cells.

A

Intrinsic factor is secreted by parietal cells.

31
Q

What is present in higher concentration in the stomach: heptacorrin or intrinsic facto?

A

Intrinsic factor

(heptacorring is higher in saliva.)

32
Q

The most ptent stimuli for HCl production by the parietal cells are:

  • [] - Enteric NS
  • [] - from G-cells
  • [] - paracrine relationship
A
  • Acetylcholine - Enteric NS
  • Gastrin - from G-cells
  • Histamine - paracrine relationship
33
Q

Gastrin release is inhibited as acid acts on the [] cell which then produces []

Inhibition of acid secretion is also mediated as acid in the duodenum releases [] which inhibits []cells production of acid

A

Gastrin release is inhibited as acid acts on the Somatostatin cell which then produces somatostatin

Inhibition of acid secretion is also mediated as acid in the duodenum releases Secretin which inhibits Parietal cells production of acid

34
Q

Pepsinogen/Pepsin Secretion

  • Secreted by [] cells near base of Gastric []
  • 2 types of pepsinogen Type I - []and Type II is found in the [] []
  • Pepsinogen converts itself to pepsin at pH < [] = []
A
  • Secreted by chief cells near base of Gastric Gland - 2 types of pepsinogen Type I - predominant and Type II is found in the Pyloric region
  • Pepsinogen converts itself to pepsin at pH < 5 = Autocatalytic
35
Q
  • Pepsin splits interior peptide bonds making it an []
A

endopeptidase

36
Q
  • [] is the most potent and important stimulator for pepsinogen/pepsin secretion
    • Acid triggers a local [] reflex stimulaitng chief cells
    • [] also stimulates chief cells to produce pepsinogen.
A
  • Acetylcholine is the most potent and important stimulator for pepsinogen/pepsin secretion
    • Acid triggers a local cholinergic reflex stimulaitng chief cells
    • Secretin also stimulates chief cells to produce pepsinogen.
37
Q

Haptocorrin Secretion

  • Secreted by the [] glands, thought to be by parietal cells
  • Associated with the []/[] [] Pump in some way.
  • Binds B12 in [] environment. B12:
    • Necessary cofactor in the maturation of []
    • []can store B12 for up to 6 year supply
    • Abosprtion by the [] mucosa
  • If absent = [] []… associated with
    • Achlorhydria
    • Lack of [] cells
A
  • Secreted by the Gastric glands, thought to be by parietal cells
  • Associated with the H+/K+ Proton Pump in some way.
  • Binds B12 in acid environment. B12:
    • Necessary cofactor in the maturation of RBCs
    • Liver can store B12 for up to 6 year supply
    • Abosprtion by the ileal mucosa
  • If absent = Pernicious Anemia associated with
    • Achlorhydria
    • Lack of parietal cells
38
Q

Intrinsic Factor Secretion:

  1. Secreted by [] cells
  2. Is a []
  3. Binds B12 at a [] pH
  4. Made in the [], but protects B12 in the []
  5. [] transporter in the [] that aborbs B12 bound to intrinsic factor.
A
  1. Secreted by parietal cells
  2. Is a mucoprotein
  3. Binds B12 at a nuetral pH
  4. Made in the stomach, but protects B12 in the duodenum
  5. Active transporter in the ileum that absorbs B12 bound to intrinsic factor.
39
Q

Mucus secretions:

  • 2 types of mucus
    • []: Fills the lumen
    • []: Coats the mucosa
  • Provides a physical and chemical barrer to both [] and [] enzyme contact
A
  • 2 types of mucus
    • Soluble: Fills the lumen
    • Insoluble: Coats the mucosa
  • Provides a physical and chemical barrer to both acid and digestive enzyme contact
40
Q

Peptic Ulcer Disease normally involves an increased acid secretion or bacterial infection by []

41
Q

Peptic Ulcer Disease:

  • Most often associate with interupting/inhibiting the dilatory actions of [] []
  • NSAID - [] [] []-[] [] will inhibit Prostaglandin E2 –> [] and restricted blood flow –> restricts [] access to mucosa –> [] barrier to acid on stomach lining.
A
  • Most often associate with interupting/inhibiting the dilatory actions of Prostaglandin E2
  • NSAID - non steroidal anti-inflammatory drugs will inhibit Prostaglandin E2 –> vasoconstriction and restricted blood flow –> restricts HCO3- access to mucosa –> smaller barrier to acid on stomach lining.
42
Q

Peptic Ulcer Treatment:

  • Neutralization of acid with a [] [] as Antacid:
    • Peptobismol
    • Tums
    • Ralids
    • Mylants
43
Q

Peptic Ulcer Treatment:

  • Specific treament: Blocking the [] type receptor blockers
    • decreases [] of parietal cells by []
  • Or Inihibt secretion of H+ by the []/[] [] Pump in the [] membrane of parietal cells
    • Can lead to [] [] by decreasing levels []/[]Factor –> decreased levels of B12 –> [] RBCs
A
  • Specific treament: Blocking the H2 type receptor blockers
    • decreases activation of parietal cells by histamine
  • Inihibt secretion of H+ by the H+/K+ Proton Pump in the apical membrane of parietal cells
    • Can lead to Pernicous Anemia by decreasing levels Heptacorrin/Instrinsic Factor –> decreased levels of B12 –> rounded RBCs
44
Q

Cephalic Phase - Effects on Gastric Acid Secretion

  • The vagus stimultes [] cells directly
    • [] is the neurotransmitter stimulating the release of gastrin via []
  • If the vagus nerve is cut above the stomach…gastric acid secretion will []
A
  • The vagus stimulates parietal cells directly
    • ACh is the neurotransmitter stimulating the release of gastrin via GRP
  • If the vagus nerve is cut above the stomach…gastric acid secretion will stop
45
Q

Gastric Phase (Digestion) Effect on Gastric Secretion:

  • Neural input via
    • [] phase influence
    • [] reflex
    • Distention
  • Chemical changes in the stomach
    • Peptides, amino acids ([] and [])
  • Secretagogues
    • [], [], and []
A
  • Neural input via
    • Cephalic phase influence
    • Vaovagal reflex
    • Distention
  • Chemical changes in the stomach
    • Peptides, amino acids (Phenylalanine and Tryptophan)
  • Secretagogues
    • Calcium, Caffeine, alcohol
46
Q

Intestinal Phase & Gastric Secretions:

  • Very [] component to gastric secretions
  • Stimulated by products of [] digestion in the []
    • Mediated by [] and []
A
  • Very minor component to gastric secretions
  • Stimulated by products of protein digestion in the duodenum
    • Mediated by Enterooxynitin and distention
47
Q

Enterooxynitin

  • Secreted by [] cells in the duodenum
  • Target is the [] Gland in the stomach, primarily p[] cells
  • Causes [] secretion
A
  • Secreted by Endocrine cells in the duodenum
  • Target is the Oxynitic Gland in the stomach, primarily parietal cells
  • Causes H+ secretion
48
Q

Pancreatic Secretions:

  • Exocrine Secretions
    • []/Aqeuous component
      • Produced by [] cells
      • [] volume
    • Enzyme component
      • produced by [] cells
      • [] volume
A
  • Exocrine Secretions
    • HCO3-/Aqeuous component
      • Produced by ductal cells
      • High volume
    • Enzyme component
      • produced by Acinar cells
      • Low volume
49
Q

3 way to regulate pancrease exocrine secretion:

  1. [] Polypeptide
  2. [] Efferents
  3. [] Efferents
A
  1. Pancreatic Polypeptide
  2. Sympathetic Efferents
  3. Parasympathetic Efferents
50
Q

Regulating Pancreatic Exocrine Secretions

  • Pancreatic Polypeptide
    • released in response to [] Acids
    • [] exocrine functions.
  • Sympathetic Efferents
    • [] exocrine secretions
    • Post-ganglionic fibers arise from: [] Plexus and Superior [] Plexus
  • Parasympathetic Efferents
    • Innervation comes from the[] nerve
    • Terminates at the []
    • [] exocrine secretions.
A
  • Pancreatic Polypeptide
    • released in response to Amino Acids
    • Inhibits exocrine functions.
  • Sympathetic Efferents
    • Inhibit exocrine secretions
    • Post-ganglionic fibers arise from: Celiac Plexus and Superior Mesenteric Plexus
  • Parasympathetic Efferents
    • Innervation comes from the Vagus nerve
    • Terminates at the acini
    • Stimulates exocrine secretions.
51
Q

Aqueous Pancreatic Secretions

  • [] with plasma
  • Cl- and HCO3- amounts vary [] due to [] [] present on membrane
  • Secreted by [] and centroacinar cells; set up by
    • Na+/K+ ATPase in [] membrane
    • [] Anhydrase
  • Regulation through [] initiated mechanism in the duodenum
A
  • Isotonic with plasma
  • Cl- and HCO3- vary inversely due to anion exchangers present on membrane
  • Secreted by ductal and centroacinar cells; set up by
    • Na+/K+ ATPase in basolateral membrane
    • Carbonic Anhydrase
  • Regulation through acid initiated mechanism in the duodenum
52
Q

Enzyme Component of Pancreatic Secretions

  • Types of Enzymes: Lipase, Amylase, and [] produced as [] precursors
  • Enzymes stored at [] granules near the [] membrane
  • Enzymes released by [] controlled by
    • [] input and [] input
  • Mediated through [] and [] in the duodenum
A
  • Types of Enzymes: Lipase, Amylase, and proteases produced as inactive precursors
  • Enzymes stored at zymogen granules near the apical membrane
  • Enzymes released by exocytosis controlled by
    • Neural input and hormonal input
  • Mediated through fat and protein in the duodenum
53
Q

Cephalic Phase & Pancreatic Secretion:

  • Vagal efferents synapse on acinus, primarily the [] cells
  • Drive [] of enzymes
    • [] can also drive secretion of enzymnes becuase its chemical structure is similar to CCK
A
  • Vagal efferents synapse on acinus, primarily the acinar cells
  • Drive secretion of enzymes
    • Gastrin can also drive secretion of enzymnes becuase its chemical structure is similar to CCK
54
Q

Gastric Phase and Pancreatic Secretions:

  • [] of stomach produces vagovagal reflex.
    • primarily acts to [] enzymatic secretion
    • Little effect on []/[] secretions (aqeuos)
A
  • Distention of stomach produces vagovagal reflex.
    • primarily acts to increase enzymatic secretion
    • Little effect on H2O/HCO3- secretions (aqeuos)
55
Q

Intestinal Phase and Pancrease Secretions:

  • provides the [] stimulus for secretion
  • Primary Agents
    • [] - form S-cells
    • [] - from I-cells
    • [] via Vagovagal reflexes
A
  • provides the most stimulus for secretion
  • Primary Agents
    • Secretin - form S-cells
    • Cholecystokinin - from I-cells
    • Acetylchoine via Vagovagal reflexes
56
Q

Intestinal Phase and Pancreatic Secretion: Mechanism

  • pH < 4.5
    • Stimulates []-cells of duodenal mucosa to produce secretin
    • Secretin stimulates [] of aqueous component
  • Fats/Proteins/H+
    • stimulate []-cells ofo duodenum to produce CCK
    • CKK increases the [] component of secretion
  • Acetylcholine
    • Acts via [] (Vagovagal) of H+, fatty acids, peptides, amino acids.
    • Increases [] component of secretion
A
  • pH < 4.5
    • Stimulates S-cells of duodenal mucosa to produce secretin
    • Secretin stimulates release of aqueous component
  • Fats/Proteins/H+
    • stimulate I-cells ofo duodenum to produce CCK
    • CKK increases the enzymatic component of secretion
  • Acetylcholine
    • Acts via chemoreception (Vagovagal) of H+, fatty acids, peptides, amino acids.
    • Increases enzymatic component of secretion
57
Q
  • Choleresis - parenchymal secretion of lipid/bile against the concentration gradient?
  • Choleretic - a substance that increases Bile Flow
58
Q

Bile Salts/Acid

  • Synthesis is mediated by the cytoplasmic enzyme []
  • Derivative of []
  • Hydrophilic and Hydrophobic = []
A
  • Synthesis is mediated by the cytoplasmic enzyme 7à-Hydroxylase
  • Derivative of cholesterol
  • Hydrophilic and Hydrophobic = amphipathic
59
Q
  • [] Bile Acids are formed by the Liver, from scratch
    • the 2 we know: [] Acid and [] Acid
  • [] Bile Acids are formed by [] bacteria from teh primary Bile Acids
    • The 2 we know: [] Acid and [] Acid
A
  • Primary Bile Acids are formed by the Liver, from scratch
    • the 2 we know: Cholic Acid and Chenodeoxycholic Acid
  • Secondary Bile Acids are formed by GI bacteria from the primary Bile Acids
    • The 2 we know: Deoxycholic Acid and Lithocholic Acid
60
Q

Lithocholic Acid

  • Only Bile Acid that can be []by the liver
    • This will not be []
    • The predominant Bile Acid in []
A
  • Only Bile Acid that can be sulfonated by the liver
    • This will not be reabsorbed
    • The predominant Bile Acid in feces
61
Q

T/F

The primary bile acids are not reabsorbed in the intestines and are predominately found in feces.

A

FALSE

This is describing lithocholic acid…which is a secondary bile acid.

62
Q

Liver Ductal Cells

  • Secrete [] and [] which are an ultrafiltrate of plasma
  • Stimulated by [] to produce HCO3-
A
  • Secrete H2O and electrolytes which are an ultrafiltrate of plasma
  • Stimulated by Secretin to produce HCO3-
63
Q

Regulation of Bile secretion - Enterohepatic Circulation:

  1. Accounts for [] of Bile salt secretion
  2. [] reabsorption from intestine
  3. [] reabsorption from [] ileum
  4. entire bile salt pool may be [] several times/meal
A
  1. Accounts for most of Bile salt secretion
  2. Passive reabsorption from intestine
  3. Active reabsorption from terminal ileum
  4. entire bile salt pool may be recirculated several times/meal
64
Q

Secretion of Bile (from liver) is increased by:

  1. [] stimulation ([] phase)
  2. [] hormone
  3. Increasd liver [] flow
A
  1. Vagal stimulation (Cephalic phase)
  2. Secretin hormone
  3. Increasd liver blood flow
65
Q

Enterohepatic Regulation of Bile Production

  • Senses Primary/secondary bile acids return from enterohepatic circulation
  • Centered on regulating the [] enzyme via the [] [] []
  • [] of Nuclear Receptor FXr ->[] gene expression of 7à-Hydroxylase ->
  • decreased production fo newly []primary bile acids –> [] of existing primary and secondary bile acids.
A
  • Senses Primary/secondary bile acids return from enterohepatic circulation
  • Centered on regulating the 7à-Hydroxylase enzyme via the Nuclear Receptor FXR
  • Activation of Nuclear Receptor FXr -> Decreased gene expression of 7à-Hydroxylase ->
  • decreased production of newly synthesized primary bile acids –> secretion of existing primary and secondary bile acids.
66
Q

Intestinal Secretions

  • Mucus
    • released by [] cells through [] & exocytosis processes
    • Increased secretion by:
      • [] NS
      • [] hormone
      • [] Reflexes (Mechano/Chemo)
A
  • Mucus
    • released by goblet cells through exfoliation & exocytosis processes
    • Increased secretion by:
      • Parasympathetic NS
      • Secretin hormone
      • Tactile Reflexes (Mechano/Chemo)
67
Q

Intestinal Secretions:

  • Electrolytes
    • serves as vehicle for []
    • Secretion [] during digestive phase
A
  • serves as vehicle for reabsorption
  • Secretion increases during digestive phase
68
Q

Intestinal Secretions:

  • Hormones:
    • [] - stimulates electrolyte secretion
    • [] - stimulate enzymatic secretion
A
  • Hormones:
    • Secretin - stimulates electrolyte secretion
    • CCK - stimulate enzymatic secretion
69
Q

Intestinal Secretions:

  • Extracellular Enzymes
    • [] (enterokinase)
      • converts trypsinogen (comes from []) into []
    • []-amylase
  • Brush Border
    • [] step in digestion
    • Tons of enzymes: peptidases, lipase, sucrase, maltase, lactase
A
  • Extracellular Enzymes
    • Enteropeptidase (enterokinase)
      • converts trypsinogen (comes from pancrease) into trypsin
    • alpha-amylase
  • Brush Border
    • Last step in digestion
    • Tons of enzymes: peptidases, lipase, sucrase, maltase, lactase
70
Q

Secretory Diarrheal Dysfunction:

  • Typically caused by [] bacteria
    • Permanetly [] adenyl cyclase elevating crypt levles of []
    • Activates brush border [] channel and deactivates [] on basolateral side
    • Na+ and Cl- secrete, taking [] with them.
    • Can poop out [] L/day
    • Best treatment - []
A
  • Typically caused by Cholera bacteria
    • Permanetly activates adenyl cyclase elevating crypt levles of cAMP
    • Activates brush border Cl- channel and deactivates Na+ pump on basolateral side
    • Na+ and Cl- secrete, taking water with them
    • Can poop out 20 L/day
    • Best treatment - rehydration
71
Q

Colonic Secretions:

  • Mucus high in [] and [] and comes from []cells
  • Functions to main [], [], and bind [] together
  • Regulated
    • Local [] reflex
    • Parasympathetic NS [] secretion (form pelvic nerve)
    • Sympathethetic NS [] secretion (from pelvic nerve)
A
  • Mucus high in K+ and HCO3- and comes from goblet cells
  • Functions to maintain neutrality, lubricate, and bind feces together
  • Regulated
    • Local intrinsic reflex
    • Parasympathetic NS increase secretion (form pelvic nerve)
    • Sympathethetic NS decrease secretion (from pelvic nerve)

Dental Physio (36 decks)

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