Mechanical stretching induces interleukin-8 gene expression in fetal membranes: a possible role for the initiation of human parturition.
OBJECTIVE
Interleukin-8 (IL-8) is known to play a crucial role in human parturition. We aimed to study the effect of mechanical stretching on the expression of IL-8 in fetal membranes (amniochorion) and decidua.


METHODS
We examined the expression of IL-8 and its receptor in fetal membranes (amniochorion) and decidua by immunohistochemical staining. Also, we studied the synthesis of IL-8 messenger RNA (mRNA) in the fetal membranes before and after stretching.


RESULTS
We found that mechanical stretching within physiological limit increased IL-8 messenger RNA (mRNA) synthesis in fetal membranes and decidua in a time- and load-dependent manner. Application of mechanical force led to markedly increased staining of IL-8 receptor in decidual cells but not in amnion or chorion cells.


CONCLUSIONS
These results suggested that mechanical stretching was a candidate for one of the signals important for production of IL-8 in fetal membranes and decidua and probably for initiation of a cytokine network at amniochorio-decidual interface through increased expression of IL-8 receptors.
Maehara
K
K
Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Japan.
Kanayama
N
N
Maradny
E E
EE
Uezato
T
T
Fujita
M
M
Terao
T
T
D000650:Amnion / Q000737:chemistry / Q000502:physiology; D015703:Antigens, CD / Q000032:analysis / Q000378:metabolism; D001696:Biomechanical Phenomena; D002823:Chorion / Q000737:chemistry / Q000502:physiology; D003656:Decidua / Q000737:chemistry / Q000502:physiology; D005321:Extraembryonic Membranes / Q000502:physiology*; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D016209:Interleukin-8 / Q000032:analysis / Q000235:genetics*; D007700:Kinetics; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis; D018123:Receptors, Interleukin / Q000032:analysis / Q000378:metabolism; D023062:Receptors, Interleukin-8A
D015703:Antigens, CD; D016209:Interleukin-8; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D023062:Receptors, Interleukin-8A