Summary
Co-activation of pro-coagulatory pathways in sepsis may result in disseminated intravascular
coagulation and contributes to microvascular dysfunction. We investigated the effects
of the direct thrombin inhibitor, argatroban (ARG), on the sepsis-induced impairment
of the intestinal microcirculation (capillary perfusion, leukocyte adhesion) and the
vascular contractility in rats. Forty male Lewis rats were randomly assigned to one
of four groups: sham surgery (SHAM), experimental sepsis (colon ascendens stent peritonitis
– CASP), CASP+ARG, and SHAM+ARG. At 16 hours after colon stent insertion (or sham
surgery), 2 mg/kg argatroban or buffer were given intravenously, and 1 hour thereafter,
intravital microscopy was performed. In addition, experiments to study the impact
of ARG on vascular contractility were conducted in vitro. ARG administration in CASP rats significantly increased functional capillary density
in mucosal (+128%) and muscular layers (longitudinal: +42%; circular: +64%) and decreased
the number of firmly adhering leukocytes in the intestinal submucosa compared to untreated
animals. In vitro findings indicated a vasodilating effect of ARG. ARG administration during experimental
sepsis improved intestinal microcirculation by preserving functional capillary density,
an indicator of microvascular perfusion, and by reducing leukocyte adherence to the
endothelium in submucosal venules.
Keywords
Inflammation - argatroban - sepsis - leukocytes - microcirculation