Effects of dopexamine on regional blood flow and leukotriene production in multiple splanchnic sites in endotoxemic rats.

This work examines the effects of lipopolysaccharide (LPS) on splanchnic blood flow and tests the potential effect of dopexamine in preventing LPS-induced decrease in splanchnic blood flow, also analyzing its influence on regional leukotriene production. Male Sprague-Dawley rats were grouped and subjected to i.v. administration (time 0) of the lipopolysaccharide (10mg/kg) or vehicles with some rats receiving dopexamine (2microg/kg/min) (times 2 hrs to 6 hrs) infusion and compared. Microdialysis collection for analyzing leukotrienes concentrations and direct splanchnic laser Doppler flowmetry were started at times 0 to 6 hrs. Mean arterial pressure decreased markedly in LPS-injected animals and it decreased further gradually during observation period. A marked increase in mean arterial pressure was noted following concomitant administration of dopexamine with LPS. Impaired splanchnic blood flow in the stomach, jejunum and ileum after LPS injection has been attenuated following infusion of dopexamine. The changes in regional blood flow in the specific splanchnic area correlate closely with the systemic mean arterial pressure in this early sepsis model. Increased leukotriene production following LPS injection also has been attenuated in the stomach, jejunum and ileum following dopexamine infusion, and the increase of leukotriene production also correlates closely with systemic mean arterial pressure.