(15S)-15-methyl prostaglandin E1-induced neutrophilia in Brown-Norway rats.

A stable analogue of prostaglandin E1, (15S)-15-methyl prostaglandin E1 (M-PGE1), induces a marked relative and absolute neutrophilia after subcutaneous injection at a pharmacologic dose of 1 mg/kg in Brown-Norway rats. The neutrophils reached a peak of 6 hours after injection at which time the absolute neutrophil count was 13,457 +/- 6,038/mm3 versus 2,451 +/- 1,298/mm3 before injection (p less than 0.001). The absolute white blood cell count/mm3 did not change significantly at 6 hours after injection, but a significant eosinopenia was noted, as has been described by previous investigators, after the administration of prostaglandins. A possible physiologic in vivo role for prostaglandin in the causation of neutrophilia remains to be elucidated.