The appearance and disappearance of PMN^BrdUin the circulation after IV IL-8 (2.5 μg/kg) (n = 5) or saline (n = 4). (A) Shows all the PMN^BrdU. In both groups there was a slow increase between 0 and 12 hours followed by a rapid increase to peak levels between 36 and 48 hours and then a slow decline over the following 5 days. G3 cells (representing the transit time through the postmitotic pool) peaked at 36 hours (B) and G1 cells (representing the transit time through both the mitotic and postmitotic pools) peaked between 96 and 120 hours in both group (C). No differences were apparent between groups. Values are mean ± SEM.