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


CONCLUSIONS
Histamine appears to induce IL-6 production through H1R in human amnion cells.
Morimitsu
Akiko
A
Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
Sumigama
Seiji
S
Kotani
Tomomi
T
Mano
Yukio
Y
Suzuki
Kanako
K
Araki-Taguchi
Masako
M
Yamamoto
Eiko
E
Hayakawa
Hiromi
H
Okada
Mayumi
M
Itakura
Atsuo
A
Kikkawa
Fumitaka
F
D000650:Amnion / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D015153:Blotting, Western; D003990:Dibenzoxepins / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006632:Histamine / Q000276:immunology / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000276:immunology; D000069605:Olopatadine Hydrochloride; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011969:Receptors, Histamine H1 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D011970:Receptors, Histamine H2 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D003990:Dibenzoxepins; D006634:Histamine H1 Antagonists; D015850:Interleukin-6; D012333:RNA, Messenger; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D000069605:Olopatadine Hydrochloride; D006632:Histamine