Noninvasive high-speed photoacoustic tomography of cerebral hemodynamics in awake-moving rats

J Cereb Blood Flow Metab. 2015 Aug;35(8):1224-32. doi: 10.1038/jcbfm.2015.138. Epub 2015 Jun 17.

Abstract

We present a noninvasive method of photoacoustic tomography (PAT) for imaging cerebral hemodynamics in awake-moving rats. The wearable PAT (wPAT) system has a size of 15 mm in height and 33 mm in diameter, and a weight of ~8 g (excluding cabling). The wPAT achieved an imaging rate of 3.33 frames/s with a lateral resolution of 243 μm. Animal experiments were designed to show wPAT feasibility for imaging cerebral hemodynamics on awake-moving animals. Results showed that the cerebral oxy-hemoglobin and deoxy-hemoglobin changed significantly in response to hyperoxia; and, after the injection of pentylenetetrazol (PTZ), cerebral blood volume changed faster over time and larger in amplitude for rats in awake-moving state compared with rats under anesthesia. By providing a light-weight, high-resolution technology for in vivo monitoring of cerebral hemodynamics in awake-behaving animals, it will be possible to develop a comprehensive understanding on how activity alters hemodynamics in normal and diseased states.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Blood Flow Velocity / drug effects
  • Blood Flow Velocity / physiology
  • Cerebrovascular Circulation / drug effects
  • Cerebrovascular Circulation / physiology*
  • GABA Antagonists / pharmacology
  • Hyperoxia / physiopathology
  • Locomotion / drug effects
  • Locomotion / physiology*
  • Male
  • Pentylenetetrazole / pharmacology
  • Photoacoustic Techniques*
  • Rats
  • Rats, Sprague-Dawley
  • Wakefulness / drug effects
  • Wakefulness / physiology*

Substances

  • GABA Antagonists
  • Pentylenetetrazole