Pharmacologically-induced neurovascular uncoupling is associated with cognitive impairment in mice

J Cereb Blood Flow Metab. 2015 Nov;35(11):1871-81. doi: 10.1038/jcbfm.2015.162. Epub 2015 Jul 15.

Abstract

There is increasing evidence that vascular risk factors, including aging, hypertension, diabetes mellitus, and obesity, promote cognitive impairment; however, the underlying mechanisms remain obscure. Cerebral blood flow (CBF) is adjusted to neuronal activity via neurovascular coupling (NVC) and this mechanism is known to be impaired in the aforementioned pathophysiologic conditions. To establish a direct relationship between impaired NVC and cognitive decline, we induced neurovascular uncoupling pharmacologically in mice by inhibiting the synthesis of vasodilator mediators involved in NVC. Treatment of mice with the epoxygenase inhibitor N-(methylsulfonyl)-2-(2-propynyloxy)-benzenehexanamide (MSPPOH), the NO synthase inhibitor l-NG-Nitroarginine methyl ester (L-NAME), and the COX inhibitor indomethacin decreased NVC by over 60% mimicking the aging phenotype, which was associated with significantly impaired spatial working memory (Y-maze), recognition memory (Novel object recognition), and impairment in motor coordination (Rotarod). Blood pressure (tail cuff) and basal cerebral perfusion (arterial spin labeling perfusion MRI) were unaffected. Thus, selective experimental disruption of NVC is associated with significant impairment of cognitive and sensorimotor function, recapitulating neurologic symptoms and signs observed in brain aging and pathophysiologic conditions associated with accelerated cerebromicrovascular aging.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Pressure / drug effects
  • Cerebrovascular Circulation / drug effects
  • Cognition Disorders / chemically induced*
  • Cognition Disorders / psychology*
  • Cyclooxygenase Inhibitors / pharmacology
  • Cytochrome P-450 CYP2J2
  • Cytochrome P-450 Enzyme System / drug effects
  • Enzyme Inhibitors / pharmacology
  • Evoked Potentials, Somatosensory / drug effects
  • Gait / drug effects
  • Hand Strength
  • Indomethacin / pharmacology
  • Male
  • Maze Learning / drug effects
  • Memory / drug effects
  • Mice
  • Mice, Inbred C57BL
  • NG-Nitroarginine Methyl Ester / pharmacology
  • Neurovascular Coupling / drug effects*
  • Nitric Oxide Synthase Type I / antagonists & inhibitors
  • Postural Balance / drug effects
  • Recognition, Psychology / drug effects

Substances

  • Cyclooxygenase Inhibitors
  • Enzyme Inhibitors
  • Cytochrome P-450 Enzyme System
  • Nitric Oxide Synthase Type I
  • Cytochrome P-450 CYP2J2
  • NG-Nitroarginine Methyl Ester
  • Indomethacin