title: [Vasoactive substances and the modulation of the hepatic microvascular system].
abstract: OBJECTIVE
  To review some aspects of the hepatic phylogeny and ontogeny, the hepatic microvascular system, and the modulation of the tonus on this vascular system by different vasoactive substances.
  
  
  METHODS
  Text books and articles from MEDLINE-indexed journals were consulted.
  
  
  RESULTS
  Fifty-two articles, that were published between 1949 and 1997, were selected. They provided us with information concerning hepatic phylogeny and ontogeny, the hepatic microvascular system, and the modulation of the tonus in this vascular system.
  
  
  CONCLUSIONS
  The architecture of the hepatic microvascular system, a unique and complex vascular system, is well suited to the functions of the organ. Different factors, including endothelial vasoactive substances, participate in the modulation of the vascular resistance through the liver adequating the liver perfusion to the homeostatic needs. The liver is eminently a maintainer of internal stability.
authors.affiliation: Departamento de Medicina e Bioquímica da Universidade Federal de São Paulo.
authors.forename: M R
authors.initials: MR
authors.lastname: Loureiro-Silva
authors.forename: H M
authors.initials: HM
authors.lastname: Molina
authors.forename: D R
authors.initials: DR
authors.lastname: Borges
mesh_terms: D000809:Angiotensins / Q000502:physiology; D001685:Biological Factors / Q000502:physiology*; D001920:Bradykinin / Q000502:physiology; D016232:Endothelins / Q000502:physiology; D011464:Epoprostenol / Q000502:physiology; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D008099:Liver / Q000098:blood supply* / Q000502:physiology*; D008833:Microcirculation; D009569:Nitric Oxide / Q000502:physiology; D010802:Phylogeny; D014664:Vasodilation / Q000502:physiology*
chemical_list: D000809:Angiotensins; D001685:Biological Factors; D016232:Endothelins; D009569:Nitric Oxide; D011464:Epoprostenol; D001920:Bradykinin