Abstract
The effect of spermidine, a type of polyamine present in exudates from inflamed tissues and bacteria-infected sites in humans, on calcium mobilization of leukotriene B4 (LTB4)-stimulated chicken abdominal macrophages and heterophils was examined in vitro. The intracellular calcium ion concentration [Ca2+]i was elevated immediately and reached a maximum a few seconds after the addition of LTB4. The elevated [Ca2+]i returned to the basal (resting) level approximately 2min after LTB4 addition. Pretreatment of cells with spermidine significantly prolonged the duration of [Ca2+]i elevation in LTB4-treated chicken phagocytes. However, no change was induced in the level of [Ca2+]i elevation by pretreating the LTB4-treated cells with spermidine. These results suggest that polyamines would enhance the activities of chicken macrophages and heterophils in inflammation sites and bacteria-infected sites through delaying the return to resting levels of stimulated cells, as in the case of human polymorphonuclear leukocytes.
