Histamine stimulates interleukin-6 production through histamine H1 receptors in human amnion cells.

BACKGROUND/AIMS: Previous studies have stated that maternal allergic diseases are associated with increased risk of preterm labor/delivery, but the underlying mechanisms remain unclear. This study tested the hypothesis that histamine induces interleukin (IL)-6 production in amnion cells.

METHODS

Using cultured human amnion cells, we examined expression of histamine receptors and effects of histamine on IL-6 production.

RESULTS

Reverse transcription-polymerase chain reaction and Western blotting revealed expression of histamine H1 receptor (H1R) and H2 receptor (H2R) in human amnion. Histamine stimulation significantly increased concentrations of IL-6 in conditioned medium, as did tumor necrosis factor-alpha and IL-1beta in positive controls. In addition, the H1R antagonist olopatadine significantly blocked histamine-induced production of IL-6, whereas the H2R antagonist ranitidine did not.

CONCLUSION

Histamine appears to induce IL-6 production through H1R in human amnion cells.