title: Effect of fractions of water extract from peat with a specific molecular weight on the spontaneous contractile activity of guinea pig stomach smooth muscles.
abstract: OBJECTIVE
  Peat and water extracts from peat have been reported in the literature to have an effect on the spontaneous contractile activity of certain smooth muscles. The purpose of the present study was to investigate the effect of organic substances of various molecular weight contained in the water peat extracts on the spontaneous contractile activity of smooth muscles.
  
  
  METHODS
  Using Amicon Centriprep molecular filters the substances contained in the water extracts from peat were separated into fractions of various molecular mass. Their effect on spontaneous contractile activity was studied on strips of guinea pig stomach.
  
  
  RESULTS
  All fractions containing the low-molecular weight component of the water peat extract (under 3000 Da) showed an excitatory effect on smooth muscle spontaneous contractile activity. The spontaneous contractile activity of smooth muscles was not influenced by the microelements Ba, Mn, and Cu applied in doses equal to the original water peat extract.
  
  
  CONCLUSIONS
  The excitatory effect of water peat extracts on the spontaneous contractile activity of smooth muscles is due to the organic compounds with molecular weight under 3000 Da.
authors.affiliation: Department of Physics and Biophysics, Higher Medical Institute, Plovdiv, Bulgaria.
authors.forename: P I
authors.initials: PI
authors.lastname: Zagorchev
authors.forename: A M
authors.initials: AM
authors.lastname: Beer
authors.forename: J B
authors.initials: JB
authors.lastname: Lukanov
mesh_terms: D000818:Animals; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D008970:Molecular Weight; D009130:Muscle, Smooth / Q000502:physiology*; D012987:Soil / Q000032:analysis*; D013270:Stomach / Q000502:physiology*; D014867:Water / Q000032:analysis* / Q000494:pharmacology*
chemical_list: D012987:Soil; D014867:Water