Low-intensity light induces vasorelaxation: a study for possible mechanism

Yuji M.D. Morimoto, Hirotaka M.D. Matsuo, Tsunenori M.D. Arai, Makoto Kikuchi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)


To investigate the mechanism of light induced vasorelaxation, vascular tension change in normal buffer solution was compared with that in the buffer containing either the following drug: (1) guanylate cyclase inhibitor; (2) nitric oxide synthetase inhibitors and the optical isomers; and (3) vasodilating agent. The vasorelaxation caused by ultraviolet light irradiation was independent of the presence of an intact endothelium. It was inhibited by methyleneblue, but not influenced by either L-NMMA or D-NMMA. On the other hand, this vasorelaxation was enhanced by the agents containing nitro group (L-NAME, D-NAME) or sodium nitrite. These results show that the light activates guanylate cyclase, which results in the vasorelaxation. This activation was reinforced by the agents containing nitro group. We conclude that primary photochemical product, which is probably nitric oxide originated from photodissociation of nitro groups, may produce the vasorelaxation. The preliminary investigation suggests that ultraviolet irradiation may be benefit in the treatment for vasospasm.

Original languageEnglish
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
Number of pages4
Publication statusPublished - 1996
Externally publishedYes
EventLaser-Tissue Interaction VII - San Jose, CA, USA
Duration: 1996 Jan 291996 Feb 1


OtherLaser-Tissue Interaction VII
CitySan Jose, CA, USA

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Low-intensity light induces vasorelaxation: a study for possible mechanism'. Together they form a unique fingerprint.

Cite this