title: Rat liver pit cells following administration of the glycopeptide preparation (Polyerga).
abstract: OBJECTIVE
  Pit cells are specific liver population which has been shown to express NK activity against tumor and viral target cells. We investigated the influence of the glycopeptide preparation (Polyerga) as one of the biological response modifiers on liver pit cells of male Wistar rats.
  
  
  METHODS
  The number of pit cells was counted by light and electron microscopy in perfusion-fixed liver sinusoids. An electron microscopical cytochemical staining for endogenous peroxidase was done.
  
  
  RESULTS
  After a single intramuscular injection of Polyerga, a 3-to 6-fold increase in the number of pit cells was observed within a period of 1 to 7 days. Wide contact without specific junctions between pit cells and Kupffer cells was frequently detected. Granules, rod-cored vesicles and their closely related structures empty vesicles as well as hypertrophied Golgi apparatus were accumulated in the cytoplasm of pit cells next to contact surface. The number of ribosomes and polysomes in pit cell cytoplasm was significantly increased, which suggests activated protein synthesis.
  
  
  CONCLUSIONS
  These changes are considered to represent the morphological expression of pit cell activation. It is concluded that the glycopeptide preparation Polyerga can induce proliferation of activated pit cells in the rat liver.
authors: Higher Medical Institute, Department of Pathology, Stara Zagora, Bulgaria.
authors: M V
authors: MV
authors: Gulubova
authors: M G
authors: MG
authors: Ganeva
authors: M A
authors: MA
authors: Zaneva
mesh_terms: D000818:Animals; D002455:Cell Division; D004338:Drug Combinations; D006020:Glycopeptides / Q000008:administration & dosage*; D007155:Immunologic Factors / Q000008:administration & dosage*; D008099:Liver / Q000187:drug effects* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D010636:Phenols / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004338:Drug Combinations; D006020:Glycopeptides; D007155:Immunologic Factors; D010636:Phenols; C054629:polyerga neu