Back to AI Flashcard MakerEducation /USMLE - GI Flashcards Part 5

USMLE - GI Flashcards Part 5

Education25 CardsCreated 20 days ago

This deck covers key concepts related to gastrointestinal physiology and pathology, including hormone sources, actions, and regulations, as well as specific conditions and their presentations.

Glucose Dependent Insulinotropic Peptide AKA Source Location of Source Exocrine Endocrine Regulation

Gastric Inhibitory Peptide (GIP) K cells in duodenum and jejunum Exocrine: ↓ Gastric H secretion Endocrine: ↑ insulin release Secretion is ↑ by FA, AA, and oral glucose
Tap or swipe ↕ to flip
Swipe ←→Navigate
1/25

Key Terms

Term
Definition
Glucose Dependent Insulinotropic Peptide AKA Source Location of Source Exocrine Endocrine Regulation
Gastric Inhibitory Peptide (GIP) K cells in duodenum and jejunum Exocrine: ↓ Gastric H secretion Endocrine: ↑ insulin release Secretion is ↑ by FA, AA...
Vasoactive Intestinal Polypeptide Source Location of Source Action Regulation
Parasympathetic ganglia in sphincters, gallbladder and SI ↑ intestinal water and electrolyte secretion and ↑ relaxation of intestinal smooth muscle an...
VIPoma Kind of cells Presentation
non-α, non-β islet pancreatic tumors secrete VIP "WDHA" Copious Watery Diarrhea, HypoK, and Achlorhydria (no gastric acid produced)
Nitric Oxide Actions in GI tract Especially present in Implicated in what disorder
Smooth muscles relaxation Especially in lower esophageal sphincter Loss of NO secretion is implicated in achalasia
Motilin Location of Source Action Regulation Agonists? Uses of agonists?
Small Intestine Produced migrating motor complexes Secretion ↑ in fasting state Agonists like erythromycin used to stimulate intestinal peristalsis
Intrinsic Factor Source Location of Source Action
Parietal Cells in Stomach (Body) | Vit B12 binding protein

Related Flashcard Decks

Study Tips

  • Press F to enter focus mode for distraction-free studying
  • Review cards regularly to improve retention
  • Try to recall the answer before flipping the card
  • Share this deck with friends to study together
TermDefinition
Glucose Dependent Insulinotropic Peptide AKA Source Location of Source Exocrine Endocrine Regulation
Gastric Inhibitory Peptide (GIP) K cells in duodenum and jejunum Exocrine: ↓ Gastric H secretion Endocrine: ↑ insulin release Secretion is ↑ by FA, AA, and oral glucose
Vasoactive Intestinal Polypeptide Source Location of Source Action Regulation
Parasympathetic ganglia in sphincters, gallbladder and SI ↑ intestinal water and electrolyte secretion and ↑ relaxation of intestinal smooth muscle and sphincters Secretion is ↑ by distention and vagal stimulation Secretion is ↓ by adrenergic input
VIPoma Kind of cells Presentation
non-α, non-β islet pancreatic tumors secrete VIP "WDHA" Copious Watery Diarrhea, HypoK, and Achlorhydria (no gastric acid produced)
Nitric Oxide Actions in GI tract Especially present in Implicated in what disorder
Smooth muscles relaxation Especially in lower esophageal sphincter Loss of NO secretion is implicated in achalasia
Motilin Location of Source Action Regulation Agonists? Uses of agonists?
Small Intestine Produced migrating motor complexes Secretion ↑ in fasting state Agonists like erythromycin used to stimulate intestinal peristalsis
Intrinsic Factor Source Location of Source Action
Parietal Cells in Stomach (Body) | Vit B12 binding protein
Where is Vit B12 absorbed?
Bound to IF in terminal ileum along with bile acids
Autoimmune destruction of parietal cells leads to
Chronic gastritis and pernicious anemia
Gastric Acid Source Location of Source Action Regulation
Parietal Cells in Stomach ↓ stomach pH Secretion ↑ by Hist, ACh, Gastrin Secretion ↓ Somatostatin, GIP, prostaglandins, secretin
Gastrinoma
Gastrin secreting tumor that causes high levels of acid secretion and ulcers
Pepsin Source Location of Source Action Regulation
Chief Cells in Stomach (Body) Protein digestion Secretion is ↑ by vagal stimulation and local acid
Activation of pepsinogen
Converted to pepsin in presence of H+
Bicarb Source Location of Source Action Regulation
Mucosal cells of stomach, duodenum, salivary glands, pancreas and Brunner's Glands (in the duodenum) Neutralizes acid Secretion is ↑ from pancreatic and biliary secretion with secretin
Mucus that covers the gastric epithelium traps what?
Traps bicarb
Saliva Secreted from Stimulated by
Parotid, Submandibular and Sublingual glands | Supplied by sympathetic (β --> cAMP) and parasympathetic activity (M --> IP3)
Components of Saliva with function
Amylase digests starch Bicarb neutralizes bacterial acids Mucin lubricates food
Tonicity of Saliva
Normally hypotonic because of absorption but more isotonic with higher flow rates (less time for absorption)
How would Atropine affect parietal cells vs. G cells
Atropine --/ parietal cells | Atropine leaves G cells unaffected because the Vagus nerve releases GRP, not ACh to activate them
Brunner's Glands Location Function Hypertrophied in…
Duodenal submucosa Secrete Alkaline mucus Hypertrophied in peptic ulcer disease
Receptors on Parietal Cells
ACh --> M3 --> Gq --> IP3 --> ATPase Gastrin --> CCKB --> Gq --> IP3 --> ATPase Hist --> H2 --> cAMP --> ATPase Prostaglandins/misoprostol Receptors --> Gi --/ cAMP Somatostatin Receptors --> Gi --/ cAMP
Pancreatic Secretions Tonicity of Fluid How does [electrolyte] change with flow?
Isotonic fluid Low flow --> High [Cl] High flow --> High [HCO3]
Pancreatic Secretions | Names and Roles
α amylase --> Starch digestion (secreted in active form) Lipase. Phospholipase A, Colipase --> fat digestion Proteases Trypsinogen --> Activation of proenzymes (including trypsinogen)
Pancreatic Proteases Names Secreted as…
Trypsin, Chymotrypsin, Elastase, Carboxypeptidase | Secreted as proenzymes (zymogens)
What converts trypsinogen into trypsin
Enterokinase/enteropeptidase and then trypsin itself
Where is enterokinase/enteropeptidase secreted from?
Duodenal mucosa