Prostaglandins
(PGs) mediate cervical ripening leading to parturition. PGs are used
successfully to induce cervical ripening. However, the cell type specific expression
of PG receptor subtypes and various stromal factors important for cervical
ripening in human cervix is not known. Our objective was to investigate the
expression and localization of PG receptors EP1-4 and FP and localization of stromal
factors CTGF (connective tissue growth factor), furin, calgranulin B, ALOX12 (arachidonate 12-lipooxy-genase) and
ALOX15 in human cervical tissue from pregnant and non-pregnant women. Cervical biopsies were obtained from
non-pregnant (NP), term pregnant (TP) and post-partum (PP) women. The mRNA
expression was determined with real-time PCR, protein expression and
localization with immunohistochemistry. Our results show that the EP2 mRNA
level was higher in the PP group as compared
to TP, whereas the EP4 mRNA level was lower in the TP group as compared
to NP. Concomitantly stromal EP2 and epithelial EP3 immunoreactivity was
higher in the TP as compared to the NP group, while the EP4 immunostaining in
glands was lower in the TP as compared to the PP group. Immunostaining of
endothelial CTGF, smooth muscle furin and ALOX12, were all lower in the TP
group as compared to NP, for CTGF also the PP group was lower than NP. Endothelial
calgranulin B
immunoreactivity was higher in the PP group than the
NP group. PG receptors and stromal factors exhibit differential expression in
the cervix from women in non-pregnant and pregnant states, implying their
involvement in the process of cervical ripening.