title: [On the number and morphometrical parameters of the nucleus ambiguous neurons after the injury and regeneration of the recurrent laryngeal nerve in the rat].
abstract: OBJECTIVE
  In laryngeal nerves injuries it is essential to know the morpho-functional reorganization of the neurons which supply the larynx in order to be successful with the clinical techniques of functional reinnervation and/or orthotopic transplant. Due to the lack of this type of studies in the literature, we investigated the organization of laryngeal motoneurons in the nucleus ambiguous (NA) after the axotomy and regeneration of the recurrent laryngeal nerve (RLN) in adult rats.
  
  
  METHODS
  We used biotinylated dextran amines (BDA, 3 kDa), this fact is an innovation in the field, because this is a novel methodological approach to this model. We studied a control group of 14 animals and four experimental groups of between 10 and 16 animals each one. In the experimental groups we studied the regeneration of the axotomized nerve in four different intervals of time after the injury: 21-28 days, 42-60 days, 90-120 days, and 150-180 days. In the control group we traced the RLN without injury while in the experimental groups we traced the axotomized RLN after each regeneration interval.
  
  
  RESULTS
  The number of traced neurons in the control group was 143 +/- 38; in the experimental groups the number was always lower than in the control (21-28 days: 14 +/- 23 neurons; 42-60 days: 46 +/- 49; 90-120 days: 55 +/- 57; 150-180 days: 61 +/- 60). The morphologic parameters studied within the neuronal bodies in the experimental groups were no statistically different when compared with those in the control group.
  
  
  CONCLUSIONS
  Results show that the tracing of the RLN after its axotomy and regeneration, in the adult rat, involves a decrease in the number of traced neurons within the NA but no changes in their size or shape during the analysed periods.
authors.affiliation: Departamento de Anatomía y Embriología Humana I, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, España.
authors.forename: Arán
authors.initials: A
authors.lastname: Pascual-Font
authors.forename: Eva
authors.initials: E
authors.lastname: Maranillo
authors.forename: Teresa
authors.initials: T
authors.lastname: Vázquez
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Sañudo
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Valderrama-Canales
mesh_terms: D000818:Animals; D001679:Biogenic Amines / Q000737:chemistry / Q000627:therapeutic use*; D001710:Biotin / Q000032:analysis; D002452:Cell Count; D003911:Dextrans / Q000032:analysis; D061224:Laryngeal Nerve Injuries; D007823:Laryngeal Nerves / Q000473:pathology; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology*; D009474:Neurons / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012009:Recurrent Laryngeal Nerve / Q000473:pathology / Q000502:physiology*; D014947:Wounds and Injuries / Q000188:drug therapy
chemical_list: D001679:Biogenic Amines; D003911:Dextrans; D001710:Biotin