The Blood-Brain Barrier, Potassium, and Brain Growth

  • Richard F. Keep
  • Jianming Xiang
  • A. Lorris Betz
Part of the Advances in Behavioral Biology book series (ABBI, volume 46)

Summary

Blood-brain barrier (BBB) permeability to small polar molecules, including potassium, is increased early in rat development and this may reflect the need of the growing brain for potassium. The latter was tested by examining the effect of dexamethasone on BBB 86Rb (potassium) permeability and brain growth. This drug substantially reduced BBB 86Rb permeability in 1 day and 1 week old rats (38 and 55%) but had no significant effect in 3 and 7 week old rats. The reduction in BBB permeability in the younger age groups was accompanied by a reduction in brain growth.

Keywords

Body Growth Brain Growth Dexamethasone Treatment Brain Water Content Paracellular Pathway 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Résumé

La perméabilité de la barrière hémato-encéphalique (BHE) pour les ions tels que le potassium est plus élevée lors des premiers stades de développement chez le rat. La pénétration cérébrale accrue du potassium pourrait refléter les besoins du cerveau au cours de son développement. Cette hypothèse a été vérifiée en étudiant l’effet de la dexamethasone sur la perméablité de la BHE pour le 86Rb (potassium) et sur la croissance cérébrale. Cette substance réduit significativement la pénétration cérébrale du 86Rb chez des rats de un jour et d’une semaine (respectivement 38 et 55%) mais n’a pas d’effet significatif chez des rats de 3 ou 7 semaines. La réduction de la perméabilité de la BHE pour le potassium par la dexamethasone, observée chez les groupes d’animaux les plus jeunes, s’accompagne d’une réduction de la croissance cérébrale.

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References

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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • Richard F. Keep
    • 1
  • Jianming Xiang
    • 1
  • A. Lorris Betz
    • 1
    • 2
  1. 1.Department of Surgery (Neurosurgery)University of MichiganAnn ArborUSA
  2. 2.Departments of Pediatrics and NeurologyUniversity of MichiganAnn ArborUSA

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