Term
When isolated from CNS input, what is the enteric system still capable of? |
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Definition
Coordinate basic reflexive functions of secretion, absorption, mixing, and movement from luminal contents |
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Term
Auerbach's plexus is another name for what? |
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Definition
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Term
Meissner's Plexus is another name for what? |
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Definition
Submucosal Plexus of the Gut Wall |
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Term
The Myenteric network extends through what structures? |
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Definition
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Term
The Submucosal Plexus travels through what structures? |
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Definition
Small and Large Intestines |
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Term
How are plexuses organized in the Enteric System? |
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Definition
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Term
What interconnects ganglia and plexuses? |
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Definition
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Term
What characterizes the axons of the Enteric System? |
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Definition
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Term
The Enteric System contains what kinds of cells also found specifically in the Central Nervous System? |
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Definition
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Term
Intrinsic Projection involeves what type of neurons? |
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Definition
Intrinsic Primary Afferent Neurons (IPAN) |
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Term
Projection is via which root? |
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Definition
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Term
What kind of ganglion are involved in nociceptive projection? |
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Definition
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Term
What does SAC stand for and where are they found? |
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Definition
Stretch Activated Channels, found in Smooth Muscle |
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Term
What is the result of the activation of SACs? |
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Definition
Induces depolarization and contraction of smooth muscle |
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Term
Epithelial Cells in the GI tract respond to what kinds of signals? |
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Definition
Luminal pH, inorganic acids, short chain fatty acids, toxins, etc. |
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Term
How do intermediary epithelial cells in the GI respond to signals? |
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Definition
Secretion of 5-HT (serotonin) which activates sensory cells |
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Term
Sensory cells in the GI tract are Polymodal, meaning what? |
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Definition
Respond to multiple stimuli types |
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Term
Excitatory motoneurons in the GI use what neurotransmitters? |
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Definition
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Term
Inhibitory motoneurons use what neurotransmitters? |
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Definition
NO, ATP, Vasoactive Intestinal Peptide, Pituitary Adenyle Cyclase Activating Peptide |
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Term
How are muscle membrane potentials characterized in most GI muscle? |
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Definition
Slow waves of depolarization followed by hyperpolarization |
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Term
What sort of depolarization is required for contraction of GI muscles? |
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Definition
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Term
What is the basis of depolarization/hyperpolarization waves in GI muscle cells? |
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Definition
Interactions with interstitial cells of Cajal |
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Term
The pacemaker cells of the GI are known as what? |
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Definition
Interstitial Cells of Cajal (ICC) |
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Term
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Definition
Interposed between Motoneurons and Muscle |
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Term
Excetions in exocrine glands and GI cells are dependent on water from where? |
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Definition
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Term
What are Crypts of Lieberkuhn? |
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Definition
Enzymatic secretory glands found in the intestinal lining of the small intestine and colon |
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Term
Innervation of Crypts of Lieberkuhn causes the gland to secrete what? |
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Definition
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Term
Gastric Acid secretion in the stomach is induced by what? |
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Definition
Actions of Secretomotor cells on Parietal Cells |
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Term
Describe the action of circular muscle transmitting a bolus of food in the GI tract |
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Definition
Muscles above contract, muscle below relax, pushing the bolus down |
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Term
What is the response of IPANs to distension? |
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Definition
Activation of a chain of ascending and descending interneurons |
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Term
Ascending neurons activated by IPAN perform what function? |
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Definition
Contacts excitatory motoneurons that induce contraction of circular muscle via ICC |
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Term
Descending neurons activated by IPAN perform what function?
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Definition
Contacts inhibitory motoneurons that induce relaxation of circular muscle via ICC
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Term
How do enteric neurons affect propulsive movements in the esophagus? |
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Definition
Synpapses on the motor end plate modulate synaptic activity of skeletal muscles controlled by somatic neurons |
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Term
What nerve innervation is responsible for expansion of the stomach? |
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Definition
Parasympathetic Vagus Nerve |
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Term
While frequency of peristalsis is due to vagal imput, peristalsis amplitude is due to what? |
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Definition
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Term
Secretomotor activity is caused by what? |
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Definition
Distention and chemical stimulus due to food bolus |
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Term
What kind of interneurons activate secretomotor neurons? |
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Definition
Descending interneurons activated via IPAN |
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Term
Secretomotor neurons perform what function? |
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Definition
Induce vasodilation and CL- secretion into the lumen, inducing water movement into the lumen |
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Term
What is the result of noxious stimulus in the GI? |
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Definition
Activate IPAN, induces CL- secretion, causes massive fluid loss via diarrhea |
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Term
What modulates strength and frequency of waves in the small and large intestines? |
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Definition
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Term
Lower esophageal is largely but not exclusively controlled by what? |
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Definition
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Term
External Anal Sphincter is regulated by what? |
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Definition
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Term
The Enteric Nervous System controls all sphincters except for what? |
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Definition
Lower Esophageal and External Anal Sphincter |
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Term
The Sphincter of Oddi serves what purpose and is controlled by what? |
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Definition
Controls the passage of bile from the gallbladder and pancreatic secretions into the duodenum, regulated by Enteric Nervous System |
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Term
Preganglionic Parasympathetic cells via Vagus and Pelvic Nerve in the Enteric NS are what kind of neurotransmitter neurons? |
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Definition
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Term
Sympathetic cells in the Enteric NS are what kind of neurons? |
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Definition
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Term
Sympathetic stimuli in the enteric system generally induces what type of response? |
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Definition
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Term
Sympathetic secretion inhibitors and motility inhibitors are modulated by what? |
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Definition
Intestinofugal sensory neurons projecting into prevertebral ganglion |
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Term
What is the prevalent symptom in Hirschsprung's Disease? |
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Definition
Severe constipation among infants |
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Term
What causes Hirschsprung's Disease? |
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Definition
Mutation results in failure of neurons to develop in distal part of the bowel |
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Term
What is the primary treatment option of Hirschsprung's Disease? |
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Definition
Removal of affected part of the bowel |
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Term
What is the prevalent symptom of Irritable Bowel Syndrome? |
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Definition
Abdominal pain, altered bowel motility manifesting as constipation, diarrhea, or fluctuations between the two |
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Term
What causes irritable bowel syndrome? |
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Definition
Hyperactivity of sensory fibers |
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Term
What is the most common treatment for Irritable Bowel Syndrome? |
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Definition
No effective treatment exists |
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Term
What causes Opoid Induced Dysfunction? |
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Definition
Numerous cell expression of opioid transmitters, decreasing cholinergic release by motorneurons with opioid receptors upon endogenous opioid release |
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Term
What is the effect of opioid induced dysfunction? |
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Definition
Exogenous opioids such as morphine given for pain management results in inhibition of propulsion of bolus along intestines |
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