Intravital imaging-based analysis tools for vessel identification and assessment of concurrent dynamic vascular events

Nat Commun. 2018 Jul 16;9(1):2746. doi: 10.1038/s41467-018-04929-8.

Abstract

The vasculature undergoes changes in diameter, permeability and blood flow in response to specific stimuli. The dynamics and interdependence of these responses in different vessels are largely unknown. Here we report a non-invasive technique to study dynamic events in different vessel categories by multi-photon microscopy and an image analysis tool, RVDM (relative velocity, direction, and morphology) allowing the identification of vessel categories by their red blood cell (RBC) parameters. Moreover, Claudin5 promoter-driven green fluorescent protein (GFP) expression is used to distinguish capillary subtypes. Intradermal injection of vascular endothelial growth factor A (VEGFA) is shown to induce leakage of circulating dextran, with vessel-type-dependent kinetics, from capillaries and venules devoid of GFP expression. VEGFA-induced leakage in capillaries coincides with vessel dilation and reduced flow velocity. Thus, intravital imaging of non-invasive stimulation combined with RVDM analysis allows for recording and quantification of very rapid events in the vasculature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Flow Velocity / drug effects
  • Blood Flow Velocity / physiology*
  • Blood Vessels / anatomy & histology
  • Blood Vessels / diagnostic imaging*
  • Blood Vessels / drug effects
  • Blood Vessels / physiology
  • Claudin-5 / genetics
  • Claudin-5 / metabolism
  • Female
  • Gene Expression
  • Genes, Reporter
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Injections, Intradermal
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Microscopy, Fluorescence, Multiphoton / instrumentation
  • Microscopy, Fluorescence, Multiphoton / methods*
  • Molecular Imaging / instrumentation
  • Molecular Imaging / methods*
  • Promoter Regions, Genetic
  • Vascular Endothelial Growth Factor A / administration & dosage

Substances

  • Claudin-5
  • Cldn5 protein, mouse
  • Vascular Endothelial Growth Factor A
  • enhanced green fluorescent protein
  • vascular endothelial growth factor A, mouse
  • Green Fluorescent Proteins