title: In vivo cerebrovascular reactivity in Wistar and Fischer 344 rat strains during aging.
abstract: Basal cerebral blood flow (CBF) and CBF regulation after hypercapnia and hypotensive hemorrhage were investigated using H2 clearance in the frontal cortex of awake 2-, 14-, or 23-mo-old Wistar or Fischer 344 rats. Basal CBF decreased in old Wistar but not in mature Wistar (old 64.4 +/- 2.8, mature 87.6 +/- 2.6, young 79.6 +/- 2.2 ml.min-1 x 100 g-1) or in old Fischer 344 (old 71.9 +/- 2.9, young 73.3 +/- 1.6 ml.min-1 x 100 g-1) rats. Cerebrovascular reactivity to hypercapnia decreased in mature and old Wistar (old 2.1 +/- 0.3, mature 3.1 +/- 0.7, young 7.0 +/- 2.1 ml.min-1 x 100 g-1 x mmHg-1) but not in old Fischer 344 rats (old 4.6 +/- 1.4, young 4.9 +/- 0.9 ml.min-1 x 100 g-1 x mmHg-1). The lower limit of CBF autoregulation increased by 20 mmHg during maturation and/or aging in the two strains. Because blood gases and pH evolved similarly in both strains, we postulate that differences in cerebrovascular structure and/or function explain the differences in CBF regulation in the older representatives of the two strains.
authors.affiliation: Laboratoire de Pharmacologie Cardio-vasculaire, Faculté de Pharmacie, Université de Nancy I, France.
authors.forename: I
authors.initials: I
authors.lastname: Lartaud
authors.forename: L
authors.initials: L
authors.lastname: Bray-des-Boscs
authors.forename: J M
authors.initials: JM
authors.lastname: Chillon
authors.forename: J
authors.initials: J
authors.lastname: Atkinson
authors.forename: C
authors.initials: C
authors.lastname: Capdeville-Atkinson
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001769:Blood; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000008:administration & dosage / Q000097:blood; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003903:Deuterium / Q000378:metabolism; D005625:Frontal Lobe / Q000098:blood supply; D006339:Heart Rate; D006470:Hemorrhage / Q000209:etiology / Q000503:physiopathology; D006706:Homeostasis; D006863:Hydrogen-Ion Concentration; D007022:Hypotension / Q000150:complications; D008297:Male; D010100:Oxygen / Q000097:blood; D051381:Rats; D011916:Rats, Inbred F344; D017208:Rats, Wistar; D014655:Vascular Resistance
chemical_list: D002245:Carbon Dioxide; D003903:Deuterium; D010100:Oxygen