Monogastric GI physiology part 2

What autonomic nervous system division stimulates secretion of saliva

parasympathetic

What animals do not have enzymes within their saliva

• cattle

• dogs

• cats

True or false: simply being at rest can be considered a stimuli for salivation

True

What are the main secretions within the stomach

• mucus

• hydrochloric acid

• proteases

• hormones

The physical and chemical defense mechanisms which protect the gastric mucosa is called that what

gastric mucosal barrier

what are the pre epithelial defenses of the gastric mucosal barrier

• mucus layer

• bicarbonate secretions

What are the epithelial defenses of the gastric mucosal barrier

• cell membranes

• tight junctions

• ion pumps

• epithelial restitution

What are the post epithelial defenses of the gastric mucosal barrier

mucosal blood flow

What 3 general ligands trigger activation of the proton pump in parietal cells

• acetylcholine

• histamine

• gastrin

what are the phases of gastric acid secretion

1. cephalic phase

2. gastric phase

3. intestinal phase

In the cephalic phase the ______ nerve is stimulated to cause the _______ cell to secrete HCL

• vagus nerve

• parietal

IN the gastric phase the stretching and distension of the stomach signal for the ______ cells to secrete ______ which stimulates further secretion of HCL and other products

• G

• gastrin

In the intestinal phase the chyme enters into the duodenum and the presence of _______ releases hormones like _______ which inhibit further secretion of HCL

• lipids

• CCK

Peristalsis for the GI tract is controlled by the ________

myenteric reflex

What are the 3 major phases of swallowing

1. oropharyngeal phase

2. esophageal phase

3. gastroesophageal phase

What are the stages within the oropharyngeal phase

1. oral stage

2. pharyngeal phase

3. cricopharyngeal phase

What are the steps for the oral stage

1. prehension

2. mastication

3. bolus formation

4. delivery to pharynx

What muscles make up the upper esophageal sphincter

cricopharyngeal muscles

What form of bolus ahs the best likelihood of stimulating a swallow response

a solid bolus

During the esophageal phase primary peristalsis is initiated in the ________

pharynx

After primary peristalsis local _________ signals for clean up and activates a __________ perastalsis

• esophageal

• secondary

Because the stomach contains _________ the LES must remain closed to prevent any refulx

positive pressure

What empty’s faster liquid or solids from the stomach

liquid

what dietary and neural factors will delay gastric emptying

• sympathetic system

• fat

• protein

• acidity

• increased osmolality

What occurs during a fasting state and sweeps undigested debris from the stomach through the intestines

Migrating motor complex

Opioids ________ segmental contractions and ________ intestinal secretions

• increase

• decrease

What are the 4 types of colonic motility

1. segmentation

2. mass movement

3. defecation

4. gastrocolic reflex

Stomach distension causing mass movement in the coon is known as the _______

gastrocolic reflex

What are the steps to vomiting(emesis)

1. glottis closed

2. diaphragm moves back

3. muscles contract

4. increased pressure in stomach and proximal duodenum

What are the two general causes of vomitting

1. primary GI disease

2. extra GI disease

What are the 4 pathways to vomiting

1. abdominal viscera

2. chemoreceptor triggers

3. cerebral cortex

4. vestibular apparatus

out of the 4 pathways to vomiting which one is considered a primary GI disease

abdominal viscera

what are the common abdominal visceral receptors in cats and dog that communicate with the central vommitting center

• NK1

• 5HT3

In dogs what are the central receptors that make up the vomiting center

• NK1

• A2

In cats what are the central receptors that make up the vomiting center

• 5HT3

• A2

• NK1

In dogs what receptors are used in chemoreceptor trigger zones

• D2

• A2

• NK1

• H1

• 5HT3

In cats what receptors are used in chemoreceptor trigger zones

• A2

• NK1

• 5HT3

Unlike cats whose vestibular apparatus can directly communicate with the vomiting center dogs need to go through the ________ in order for their vestibular apparatus to interact with the vomiting center

chemoreceptor trigger zones

In both animals what receptor is used for the vestibular apparatus

M1

What are the two types of vomit

• duodenal vomit

• gastric vomiting

which type of vomit is more common for cats and dogs

duodenal vomiting

When having duodenal vomiting there is more base released alongside it causing the bicarbonate to ______ resulting in________

• drop

• metabolic acidosis

When having gastric vomiting it is more acidic to be released alongside it causing bicarb to __________ resulting in __________

• increase

• metabolic alkalosis

A dog having increased bicarb and gastric vomiting would indicate that they have what common problem

obstruction

Dogs can from intrinsic factor from what two locations

• stomach

• pancreas

cats can from intrinsic factor only from their _____

pancreas

Vitamin B12 can only be absorbed in the ________

Ileum

B12 can only be absorbed if it is bound to a ____________

Intrinsic factor

Folate can only be absorbed in the ________

proximal small intestine

High folate could indicate ________

bacterial overgrowth

Low folate could indicate __________

Disease in proximal SI(small intestine)

What are some causes of hypersalivation in animals

• nausea

• drugs

• CNS disorders

Explain why aspiration pneumonia does not typically occur with diseases involving the oral stage of swallowing.

it is far away from the trachea and epiglottic fold so no way for it to get sucked into the trachea

What hormone in dogs stimulates the activation of the Migrating motor complex

motilin

Of the two types of small intestinal motility patterns – peristalsis and segmental contractions –

which one slows intestinal transit of ingesta? What category of antidiarrheal agents promotes

increased segmental contractions?

1. segmental contractions

2. opioids