title: Ultrastructural changes in postcapillary-sized venule morphology in aged mouse periodontal ligament.
abstract: The aim of this study was to compare the postcapillary-sized venule (PCV) morphology of four young ALCA mice (35 days) and four colony-related aged mice (365 days) using the transmission electron microscope (TEM). Right and left mandibular first molar mesial roots with associated periodontal ligament (PDL) and bony socket, were used for TEM assessment. Five PCV profiles were selected at each 160 microm interval, from the alveolar crest to the tooth apex. PCV profile dimensions were measured on standardised micrographs magnified x2900. Age affects were tested using multiple regression analysis. The number of PCV profiles in the tooth third of the PDL was higher in aged mice (p < 0.01) and comprised predominantly apericytic vessels (p < 0.001). The number of PCV profiles increased significantly (p < 0.001) in aged mice in the PDL middle circumferential third halfway down the molar root. Age had no significant affect on PCV diameter. Aged PDL permeability studies are needed to investigate whether the changes in aged PCV profile number are associated with functional modification of the PDL microvasculature.
authors.affiliation: Orthodontic Unit, Dental School, The University of Adelaide, South Australia, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Cameron
authors.forename: M R
authors.initials: MR
authors.lastname: Sims
authors.forename: W J
authors.initials: WJ
authors.lastname: Sampson
mesh_terms: D000375:Aging / Q000473:pathology*; D000539:Alveolar Process / Q000098:blood supply; D000818:Animals; D002196:Capillaries / Q000648:ultrastructure*; D002199:Capillary Permeability / Q000502:physiology; D051379:Mice; D008815:Mice, Inbred Strains; D008833:Microcirculation / Q000502:physiology; D008854:Microscopy, Electron; D008963:Molar / Q000098:blood supply; D020286:Pericytes / Q000648:ultrastructure; D010513:Periodontal Ligament / Q000098:blood supply*; D012044:Regression Analysis; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D019227:Tooth Apex / Q000098:blood supply; D014092:Tooth Root / Q000098:blood supply; D020390:Tooth Socket / Q000098:blood supply; D014699:Venules / Q000648:ultrastructure*