Key Points:

• fxns

  • Ingestion

  • Digestion

  • Absorption

  • Defecation

  • Secretion

  • Motility

  • Circulation in arterioles

• Anatomy (general)

  • Mouth

  • Salivary glands

  • Esophagus

  • Stomach

  • Small/large intestine

  • Auxiliary

    • Liver

    • Pancreas

    • Gall bladder

• Circulation

  • 2 main sides

    • Spleenenic side

    • Portal side

      • LIVER

• Anatomy of GI wall

  • Mucosal layer

    • Inner

    • 3 parts

  • Submucosal layer

    • Connective tissue

  • Muscularis external

    • Muscle

    • fxn

  • Serosa

    • Outer

  • PLEXUS

    • Nerve cell bodies

• Stomach vs. small intestine

  • Mucosa

• Intestinal villus and crypt

  • Small intestine

    • Villi+ crypt

  • Large intestine

    • Just crypts

• Characteristics of SM/ Motility

  • Big idea: GI tract uses unitary smooth muscle

    • Aka…

  • Smooth muscle review

  • Slow waves

    • ICC cells

    • Set the BER

  • Spike potentials

    • Contraction

  • Muscular movements

    • Segmentation

    • Peristalsis

      • Contract, sent Inhibitory signals ahead, relax ahead

• Neural control

  • "ENTERIC"

  • How can muscles and plexxi be stimulated?

  • 2 main plexxi

    • Myenteric

      • muscle

    • Submucosal

      • Mucosa

  • Neural reflexes

    • Long

    • Short

      • Start: internal stimuli

      • End: final destination (muscle, mucosa)

• Salivation

  • Saliva components

    • 2 enzymes

  • Glands

    • Parotid

      • stimulus

    • Submandibular

    • Sublingual

  • CELLS

    • Acinar cells-->

      • Serous

      • mucous

    • Ductal cells-->

      • Fxn

• Regulation of saliva

  • Parasympathetic

  • Sympathetic

  • Example

    • Stimulus--> Ach--> 2nd mes--> acinae/ducts activated--> increase saliva

• Modification of saliva

  • ALWAYS HYPOTONIC!!!!!!!!!!

  1. Basically saliva from acinar cells = isotonic

  2. As saliva moves down duct= modified

  3. Modifications: NO h20 movement, NaCl out, K/HCO3 in

  • MORE NaCl is REMOVED THAN K/HCO3 is BROUGHT IN= HYPOTONIC

  • Flow rates

• Disorders

  • Sjogren syndrome

    • Cause

    • Symptoms

    • Tx