18 - GI Physiology 2

B

QC: Storage (1) Antrum (2) Fundus

C

QC: Chyme Formation (1) Antrum (2) Fundus

A

QC: Gastric Emptying (1) Antrum (2) Fundus

LES and cardia

This region of the stomach prevents reflux into the esophagus and regulates belching

B

QC: Contractile Strength (1) Fundus (2) Antrum

Interstitial cells of Cajal

Pacemaker one of gastric smooth muscle

A

QC: Duration of AP (1) Smooth (2) Cardiac Muscle

T

T/F: AP in smooth muscle cells have no overshoot

Myenteric Plexus

The pacemaker cells of the stomach are primarily located where?

3 slow waves/min

The basal electrical rhythm of gastric smooth muscles is?

A

QC: Gastric smooth muscle motility during activation of (1) Vagus Nerve (2) Celiac Plexus

A

VR: (1) Substance P (2) Gastric smooth muscle motility

A

VR: (1) Gastrin (2) Gastric smooth muscle motility

B

VR: (1) NE (2) Gastric smooth muscle motility

B

QC: Presence of slow waves (1) Body (2) Pylorus

Receptive Relaxation

Ability of fundus and body to receive up to a volume without an increase in intragastric pressure

C

QC: Intragastric Pressure during (1) 0.5 L (2) 1L of food

B

VR: Intragastric Pressure (1) Intact vagus (2) Vagotomy

Gastric Accommodation

This is the active dilatation of the fundus to tolerate a heavy meal

ENS

Primary regulator of gastric accommodation

3 → 1 → 5 → 4 → 6 → 2

Arrange these via which will be emptied first to last

(1) Gatorade
(2) Butter
(3) Water
(4) Solid 0.5 mm
(5) Milk
(6) Solid 3 mm

Propulsion

This is the movement of solid particles towards the antrum

Grinding

This is the churning of the bolus to reduce the size of the particles

Retropulsion

This is the movement of solid particles back to the fundus

A

QC: MMC for solids (1) >2 mm (2) <2 mm

B

QC: MMC Activation (1) Fed (2) Fasting state

A

VR: (1) Motilin (2) MMC

Cardiac glandular region

This region of the stomach is found below the LES

Pyloric Glandular region

This region of the stomach is found below the gastric notch

Oxyntic Glandular Region

This region of the stomach is found above the gastric notch

Surface epithelial cells and Mucus neck cells

Only cells present in the cardiac glandular region

A

QC: ECL cells (1) Oxyntic (2) Pyloric

C

QC: Chief cells (1) Oxyntic (2) Pyloric

A

QC: Parietal cells (1) Oxyntic (2) Pyloric

C

QC: D cells (1) Oxyntic (2) Pyloric

A

QC: Mucus (1) Neck cells (2) Surface epithelial cells

B

QC: Bicarbonate (1) Neck cells (2) Surface epithelial cells

A

QC: Somatostatin (1) D (2) G cell

B

QC: Gastrin (1) D (2) G cell

B

QC: Intrinsic Factor (1) Chief (2) Parietal cell

B

QC: HCl (1) Chief (2) Parietal cell

A

QC: Pepsinogen (1) Chief (2) Parietal cell

ECL cells

Gastric cell that secretes Histamine

B

VR: (1) Gastric juice secretion rate (2) pH

A

VR: (1) Gastric flow rate (2) Tonicity of gastric juice

Cl-

Major anion of gastric juice

A

VR: (1) Gastric flow rate (2) Cl- concentration

A

VR: (1) Gastric flow rate (2) K+ concentration

B

VR: (1) Gastric flow rate (2) Na+ concentration

A

QC: K+ in (1) Gastric juice (2) Plasma

B

QC: Tonicity (1) Gastric juice at low flow rate (2) Plasma

C

QC: Tonicity (1) Gastric juice at high flow rate (2) Plasma

B

QC: Fusion of canaliculi and tubulovesicular membrane (1) Resting (2) Active parietal cell

A

QC: Contains proton pump (1) Tubulovesicular membrane (2) Intracellular canaliculi

A

VR: (1) Carbonic Anhydrase (2) Cl- influx into parietal cell

A

QC: Cl- efflux into lumen during parietal cell (1) Hyperpolarization (2) Depolarization

A

VR: (1) Luminal Ca (2) HCl production

A

VR: (1) cAMP (2) HCl production

Proton Pump

Main pump for H+ efflux into the lumen

Cl- ion channel

Main transporter for Cl- efflux into the lumen

PSNS

Main regulator of gastric acid secretion

B

QC: Production of gastric acid (1) Intestinal (2) Gastric Phase

ACh

This is a neurocrine agonist for gastric acid secretion

Histamine

This is a paracrine agonist for gastric acid secretion

Gastrin

This is an endocrine agonist for gastric acid secretion

A

VR: (1) ACh (2) Histamine

A

VR: (1) Gastrin (2) Histamine

M3

Parietal cell receptor that ACh binds to

CCK-B/CCK-2

Parietal cell receptor that Gastrin binds to

H2

Parietal cell receptor that Histamine binds to

A

QC: ACh (1) Phospholipase C (2) Adenylyl Cyclase

A

QC: Gastrin (1) Phospholipase C (2) Adenylyl Cyclase

B

QC: Histamine (1) Phospholipase C (2) Adenylyl Cyclase

B

VR: (1) Somatostatin (2) Gastric Acid secretion

Adenylyl Cyclase

Somatostatin, PGE, PGI, and EGF all share a pathway to inhibit gastric acid secretion via inhibition of what enzyme?

A

QC: Paracrine mechanism (1) Corpus D cells (2) Antral D cells

B

QC: Endocrine mechanism (1) Corpus D cells (2) Antral D cells

A

QC: Targets histamine (1) Corpus D cells (2) Antral D cells

B

QC: Targets gastrin (1) Corpus D cells (2) Antral D cells

EP3

Receptor that PGE and PGI binds to

Gastrin and Histamine

Which agonists does PGE and PGI inhibit the release of?

B

VR: (1) Acidity of duodenal chyme (2) Gastric Acid secretion

B

QC: HCl secretion (1) Morning (2) Night

A

QC: HCl secretion (1) Men (2) Women

B

QC: Stomach pH during (1) Between meals (2) Eating a meal

B

QC: HCl secretion (1) Between meals (2) Eating a meal

Cephalic Phase

This phase is the activation of the GI tract in preparation for a meal

T

T/F: The cephalic phase is self-regulated

A

QC: Local ENS reflex (1) ACh (2) Gastrin Release

A

VR: (1) Presence of amino acids (2) Gastrin release

C

VR: (1) Presence of intact proteins (2) Gastrin release

T

T/F: The gastric phase is sefl-regulated

A

QC: Gastric Acid secretion when pH is (1) >3 (2) <3

A

VR: (1) Enterooxyntin (2) HCl release

B

VR: (1) GIP (2) HCl release

B

VR: (1) CCK (2) HCl release

B

VR: (1) Osmolarity (2) HCl release

Pepsinogen

Major digestive constituent of gastric secretion

A

VR: (1) HCl (2) Pepsinogen activation

A

VR: (1) Pepsin (2) Pepsinogen activation