Dynamic changes in water ADC, energy metabolism, extracellular space volume, and tortuosity in neonatal rat brain during global ischemia

Magn Reson Med. 1996 Jul;36(1):52-60. doi: 10.1002/mrm.1910360110.


To obtain a better understanding of the mechanisms underlying early changes in the brain water apparent diffusion coefficient (ADC) observed in cerebral ischemia, dynamic changes in the ADC of water and in the energy status were measured at postnatal day 8 or 9 in neonatal rat brains after cardiac arrest using 1H MRS/MRI and 31P MRS, respectively. The time courses of the MR parameters were compared with changes in the extracellular space (ECS) volume fraction (alpha) and tortuosity (lambda), determined from concentration-time profiles of tetramethylammonium applied by iontophoresis. The data show a decrease of the ADC of tissue water after induction of global ischemia of which the time course strongly correlates with the time course of the decrease in the ECS volume fraction and the increase in ECS tortuosity. This indicates that cell swelling is an important cause for the ADC decrease of water.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Body Water / metabolism*
  • Brain / metabolism*
  • Brain / pathology
  • Brain Ischemia / metabolism*
  • Brain Ischemia / pathology
  • Diffusion
  • Energy Metabolism*
  • Extracellular Space / metabolism*
  • Ganglionic Stimulants / metabolism
  • Heart Arrest
  • Hydrogen
  • Intracellular Fluid / metabolism
  • Iontophoresis
  • Magnetic Resonance Imaging
  • Magnetic Resonance Spectroscopy
  • Phosphorus Isotopes
  • Quaternary Ammonium Compounds / metabolism
  • Rats
  • Rats, Wistar


  • Ganglionic Stimulants
  • Phosphorus Isotopes
  • Quaternary Ammonium Compounds
  • Hydrogen
  • tetramethylammonium