Sphingosine-1-phosphate modulation of basal permeability and acute inflammatory responses in rat venular microvessels.

ABSTRACT:

Aims

Although several cultured endothelial cell studies indicate that sphingosine-1-phosphate (S1P), via GTPase Rac1 activation, enhances endothelial barriers, very few in situ studies have been published. We aimed to further investigate the mechanisms whereby S1P modulates both baseline and increased permeability in intact microvessels.

Methods and results

We measured attenuation by S1P of platelet-activating factor (PAF)- or bradykinin (Bk)-induced hydraulic conductivity (L(p)) increase in mesenteric microvessels of anaesthetized rats. S1P alone (1-5 µM) attenuated by 70% the acute L(p) increase due to PAF or Bk. Immunofluorescence methods in the same vessels under identical experimental conditions showed that Bk or PAF stimulated the loss of peripheral endothelial cortact

SUBMITTER: Adamson RH 

PROVIDER: S-EPMC2952530 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature