Histamine Release Induced by Human Leukocyte Lysates REABSORPTION OF PREVIOUSLY RELEASED HISTAMINE AFTER EXPOSURE TO CYCLIC AMP-ACTIVE AGENTS

摘要

The role of cyclic AMP in histamine release induced by human leukocyte lysates was investigated. Leukocytes were incubated with leukocyte lysates prepared by ultrasonic disruption, and histamine was determined fluorimetrically. Several cyclic AMP-active agents had a marked inhibitory effect on histamine release. Theophylline and isoproterenol produced 50% inhibition at concentrations of less than 10-5 M. Prostaglandin E1 and dibutyryl cyclic AMP inhibited release by 50% at 7 × 10-8 M and 6 × 10-5 M concentrations, respectively. Histamine, which has recently been shown to increase leukocyte cyclic AMP, had a pronounced inhibitory effect on lysate-induced histamine release, producing 50% inhibition at a concentration of only 2.5 × 10-12 M.