Interleukin-1beta and interleukin-8 concentrations in the lower uterine segment during parturition at term.
OBJECTIVE
To assess the roles of interleukin-1beta, interleukin-8, and fibroblasts in the lower uterine segment during parturition.


METHODS
Lower uterine segment biopsy specimens were obtained from 36 women undergoing cesarean delivery at various stages of cervical dilation (less than 2 cm, n = 8; 2 to less than 4 cm, n = 9; 4-6 cm, n = 10; more than 6 cm, n = 9). The concentrations of interleukin-1beta and interleukin-8 in protein extracts prepared from the tissue samples were measured by enzyme immunoassays. The effect of incubation with interleukin-1beta (30 U/mL) on interleukin-8 secretion by lower uterine segment fibroblasts in vitro also was determined.


RESULTS
The median interleukin-1beta concentration in the specimens increased from 1.3 pg/mg of total protein at less than 2 cm of dilation to 22.2 pg/mg of total protein at 4-6 cm of dilation (P < .05). No further increase was detectable after 6 cm of dilation. The interleukin-8 concentration increased from 17.2 pg/mg of total protein at less than 2 cm of dilation to 2080.7 pg/mg of total protein at 4-6 cm of dilation (P < .05), thus paralleling the increase in interleukin-1beta concentration. Interleukin-1beta induced a significant increase in interleukin-8 secretion by fibroblasts in vitro, from 0.8 ng/10(6) cells to 35.6 ng/10(6) cells.


CONCLUSIONS
The increase in interleukin-8 concentration in the lower uterine segment during parturition may be induced by interleukin-1beta and fibroblasts may be one of the sources of this interleukin-8.
Winkler
M
M
Department of Obstetrics and Gynecology and the Institute for Clinical Chemistry and Pathobiochemistry, University Hospital, Technical University, Aachen, Germany.
Fischer
D C
DC
Hlubek
M
M
van de Leur
E
E
Haubeck
H D
HD
Rath
W
W
D000328:Adult; D001706:Biopsy; D002478:Cells, Cultured; D002584:Cervix Uteri / Q000502:physiology; D002585:Cesarean Section; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D007375:Interleukin-1 / Q000032:analysis / Q000502:physiology*; D016209:Interleukin-8 / Q000032:analysis / Q000502:physiology*; D007743:Labor, Obstetric; D011247:Pregnancy; D014599:Uterus / Q000166:cytology / Q000378:metabolism*
D007375:Interleukin-1; D016209:Interleukin-8