Evidence for a pathway that facilitates nitric oxide diffusion in the brain

Ricardo M. Santos, Cátia F. Loureno, Greg A. Gerhardt, Enrique Cadenas, João Laranjinha, Rui M. Barbosa

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


Nitric oxide (NO) is a diffusible messenger that conveys information based on its concentration dynamics, which is dictated by the interplay between its synthesis, inactivation and diffusion. Here, we characterized NO diffusion in the rat brain in vivo. By direct sub-second measurement of NO, we determined the diffusion coefficient of NO in the rat brain cortex. The value of 2.2 × 10-5 cm2/s obtained in vivo was only 14% lower than that obtained in agarose gel (used to evaluate NO free diffusion). These results reinforce the view of NO as a fast diffusing messenger but, noticeably, the data indicates that neither NO diffusion through the brain extracellular space nor homogeneous diffusion in the tissue through brain cells can account for the similarity between NO free diffusion coefficient and that obtained in the brain. Overall, the results support that NO diffusion in brain tissue is heterogeneous, pointing to the existence of a pathway that facilitates NO diffusion, such as cell membranes and other hydrophobic structures.

Original languageEnglish
Pages (from-to)90-96
Number of pages7
JournalNeurochemistry International
Issue number1
StatePublished - Aug 2011


  • Brain
  • Diffusion
  • Half-life
  • In vivo
  • Microelectrode
  • Nitric oxide

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Cell Biology


Dive into the research topics of 'Evidence for a pathway that facilitates nitric oxide diffusion in the brain'. Together they form a unique fingerprint.

Cite this