title: [A preliminary study on the effects of the exogenous creatine phosphate on rat masseter muscle after unilateral chew].
abstract: OBJECTIVE
  To study the effect of energy therapy on Ca2+ concentration and Ca2+ -ATP enzyme activity in rat master muscle after unilateral chew, and to discuss the protective action of the exogenous creatine phosphate on rat masseter muscle after unilateral chew.
  
  
  METHODS
  The 20 rats were randomly divided into 4 groups, A: Creatine phosphate normal control group; B: Creatine phosphate experimental group; C: Saline normal control group; D: Saline experimental group. The Ca2+ concentration were determined by atomic absorption spectrophotometry, the activity of the Ca2+ -ATP enzyme were determined by super-micro volume Ca2+ -ATP enzyme kit.
  
  
  RESULTS
  (1) The Ca2+ concentration of the extraction side of group D which received the saline injection had significant difference compared with the non-extraction side (P = 0.007), the group C (P = 0.009) and the extraction side of group B (P = 0.01); (2) Ca2+ -ATP enzyme activity of group D were higher than its non-extraction side (P = 0.001), group C (P = 0.003) and the extraction side of group B (P = 0.001); (3) The ultrastructural changes of the rat masseter muscle under transmission electron microscope were as follows: The extraction side of group D have more severe pathological manifestations than non-extraction side. Both the extraction side and the non-extraction side of group B had a similar manifestation to the normal control group.
  
  
  CONCLUSIONS
  Exogenous energy material, creatine phosphate, may have certain degree of protective effect on rat masseter muscles after unilateral chew. And it may become a possible way to improve the injury of the masseter muscle.
authors.affiliation: Dept. of Prosthodontics, College of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Long-bo
authors.initials: LB
authors.lastname: Xu
authors.forename: Zi-xian
authors.initials: ZX
authors.lastname: Wang
authors.forename: Dong
authors.initials: D
authors.lastname: Qi
authors.forename: Xue-fen
authors.initials: XF
authors.lastname: Lin
authors.forename: Wang-gui
authors.initials: WG
authors.lastname: Ying
authors.forename: Sheng-jun
authors.initials: SJ
authors.lastname: Sun
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Ping
authors.initials: P
authors.lastname: Ji
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D008406:Masseter Muscle / Q000503:physiopathology* / Q000648:ultrastructure; D008409:Mastication; D046529:Microscopy, Electron, Transmission; D010725:Phosphocreatine / Q000494:pharmacology*; D051381:Rats
chemical_list: D010725:Phosphocreatine; D000252:Calcium-Transporting ATPases; D002118:Calcium