Small intestine Rabbit Flashcards
(11 cards)
2 Types of Intestinal Smooth muscle contraction
- Phasic contractions
- Tonic contractions
Phasic contraction
Periodic depol. caused by Cajal cells for peristalsis
Ca channel opens, Depol, K channels open, Repol, VDCC closes, slow waves
Tonic contraction
Basal contraction induced by stretching
How do we monitor the intestinal contractions
Electromechanical transducer which converts mechanical energy into electrical
Where do we keep intestines in
Tyrode’s Solution which is a physiological solution used ot keep tissues alive outside the body
- Isosomotic, Glucose, HCO3-
Effect of Hypoxia
Both frequency and amplitude of contractions are reduced, as well as force of contraction which is also reduced due to low ATP generation
Effect of ACh
ACh activates m3ACh-R (Gq) causing Ca signal, higher muscle contraction due to Gq pathway
Effect of Atropine
Atropine is a competitive inhibitor of muscarinic ACh receptor therefore less muscle contraction
Effect of Epinephrine
Binds B2-AR (Gs) causing decreased frequency and amplitude of contractions.
cAMP, MLCK phosph, inhibition, less contractions
Neostigmine
ACh Esterase inhibitor so more ACh remains at receptors so adding it causes same effects of ACh so more contractions
EDTA
Binds Ca2+ ions and reduces availability for contraction, so E.C Ca decreases causing less contraction
