0000000000341552
AUTHOR
Roy R. Lobb
Rolipram inhibits leukocyte-endothelial cell interactionsin vivothrough P- and E-selectin downregulation
1. Rolipram, a selective phosphodiesterase (PDE) type 4 inhibitor, was used to characterize leukocyte recruitment mechanisms in models of acute and subacute inflammation. Intravital microscopy within the rat mesenteric microcirculation was employed. 2. Mesentery superfusion with PAF (0.1 microM) induced a significant increase in leukocyte rolling flux, adhesion and emigration at 60 min. Rolipram pretreatment, markedly inhibited these parameters by 100, 95 and 95% respectively. 3. Similar effects were observed when the mesentery was superfused with LPS (1 microg ml(-1)) for the same time period and these leukocyte parameters were nearly abrogated by rolipram pretreatment. 4. LPS exposure of …
Direct evidence of leukocyte adhesion in arterioles by angiotensin II
AbstractAlthough leukocytes adhere in arteries in various vascular diseases, to date no endogenous proinflammatory molecule has been identified to initiate leukocyte adhesion in the arterial vasculature. This study was undertaken to assess angiotensin II (Ang II)-induced leukocyte adhesion in arterioles in vivo. Rats received intraperitoneal injections of Ang II; 4 hours later, leukocyte recruitment in mesenteric microcirculation was examined using intravital microscopy. Ang II (1 nM) produced significant arteriolar leukocyte adhesion of mononuclear cells. Using function-blocking monoclonal antibodies (mAbs) against different rat cell adhesion molecules (CAMs), we discovered that this effec…