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***This causes inhibition of the steric block keeping Actin and Myosin from interacting
 
***This causes inhibition of the steric block keeping Actin and Myosin from interacting
 
*Increased Calcium causes a negative feedback inhibition of Ca release, and it is pumped back into the sarcoplasmic reticulum by the Ca/ATPase pump
 
*Increased Calcium causes a negative feedback inhibition of Ca release, and it is pumped back into the sarcoplasmic reticulum by the Ca/ATPase pump
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 +
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==Smooth Muscle==
 +
[[Image:Smooth Muscle 1.jpg|thumb|right|150px|Smooth muscle - Copyright RVC 2008]]
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*Smooth muscle lacks troponin
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*Control of smooth muscle contraction involves '''thin and thick filament regulation'''
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* Thin filament regulation is carried out by the actin binding protein, '''Caldesmon''', which binds the thin filament and blocks myosin access
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**'''Calmodulin''' (activated by binding Ca) binds caldesmon and causes its dissociation from actin, enabling contraction
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*Thick filament regulation occurs by the '''phosphorylation''' of the '''regulatory light chain (RLC)'''
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**Calmodulin-Ca binds and activates myosin light chain kinase (MLCK)
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**MLCK then phosphorylates RLC, turning myosin on
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**Myosin light chain phosphatase (MLCP) switches myosin off
       
==Cardiac Muscle==
 
==Cardiac Muscle==
   
*Structural: striated but uninucleate, highly vascularized
 
*Structural: striated but uninucleate, highly vascularized
 
*Gap junctions concentrated at intercalated discs
 
*Gap junctions concentrated at intercalated discs
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*Action potential has a prolonged plateau phase
 
*Action potential has a prolonged plateau phase
   −
==Smooth Muscle==
  −
[[Image:Smooth Muscle 1.jpg|thumb|right|150px|Smooth muscle - Copyright RVC 2008]]
  −
*Smooth muscle lacks troponin
  −
*Control of smooth muscle contraction involves '''thin and thick filament regulation'''
  −
* Thin filament regulation is carried out by the actin binding protein, '''Caldesmon''', which binds the thin filament and blocks myosin access
  −
**'''Calmodulin''' (activated by binding Ca) binds caldesmon and causes its dissociation from actin, enabling contraction
  −
*Thick filament regulation occurs by the '''phosphorylation''' of the '''regulatory light chain (RLC)'''
  −
**Calmodulin-Ca binds and activates myosin light chain kinase (MLCK)
  −
**MLCK then phosphorylates RLC, turning myosin on
  −
**Myosin light chain phosphatase (MLCP) switches myosin off
      
==Tendon==
 
==Tendon==
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