title: Isolation of intramitochondrial helical filaments appearing in outer compartment of mitochondria.
abstract: BACKGROUND
  Packets of helical filaments have been observed in the outer compartment of occasional mitochondria in many cell types in a variety of animals. The composition and function of these intramitochondrial helical filaments (IMHF) are unknown.
  
  
  METHODS
  IMHF were induced in a hepatic mitochondria by administration of ethanol in the drinking water of rats. Hepatic mitochondria were isolated and ruptured by osmotic shock, releasing the IMHF. To purify these structures, the IMHF-containing supernatant was further fractionated by ammonium sulfate precipitation, a 50-60% solution of this reagent being the most effective in this regard. Isolated IMHF were examined by electron microscopy and were analyzed by SDS-PAGE.
  
  
  RESULTS
  Isolated IMHF closely resembled their in situ counterparts: they had a right-handed helical structure with a 16 nm pitch. SDS-PAGE analysis revealed that they contained three polypeptides with molecular weight of 135, 98, and 53 kD, respectively.
  
  
  CONCLUSIONS
  These observations will stand as a baseline for comparisons with IMHF that occur naturally or that are induced in other cell types by other kinds of experimental manipulation.
authors.affiliation: Division of Morphology, Jikei University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sasaki
authors.forename: S
authors.initials: S
authors.lastname: Kurioka
authors.forename: H
authors.initials: H
authors.lastname: Fukata
authors.forename: T
authors.initials: T
authors.lastname: Ohoki
authors.forename: H
authors.initials: H
authors.lastname: Arai
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D006652:Histological Techniques; D008297:Male; D008854:Microscopy, Electron; D008930:Mitochondria, Liver / Q000648:ultrastructure*; D051381:Rats; D017207:Rats, Sprague-Dawley