Role of leukotriene D4 in promoting proliferation of cultured human airway smooth muscle cells

AIM: To investigate whether leukotriene D₄(LTD₄) would stimulates proliferation of cultured human airway smooth muscle (ASMC). METHOD: Human ASMC were isolated and subcultured, varying concentration of LTD₄ were added to the media. Cell counts were obtained, -thymidine(³H]-TdR) incorporation and inositol 1, 4, 5-trisphosphate (IP₃) accumulation were measured. RESULTS: LTD₄(0.1nmol·L^-1~10 nmol·L^-1) increased cell number and also increased incorporation of³H]-TdR and accumulation of IP₃ in a concentration dependent manner(P＜0.01). The latter response was blocked by phospholipase C inhibition with neomycin (1 μmoL·L^-1(P＜0.01). However, neomycin had no effect on the promitogenic action of LTD₄. CONCLUSION: LTD₄ stimulates proliferation of cultured human ASMC and may play a role in airway remodeling of asthma.