Prostaglandin endoperoxide h synthase -2 expression and activity
increases with term labor in human chorion.
Mijovic, Jane E., Tamas Zakar, Travis K. Nairn, and David M. Olson.
Perinatal Research Centre, Departments of Physiology, Obstetrics
and Gynaecology, and Pediatrics, University of Alberta, Edmonton,
Alberta T6G 2S2, Canada
APStracts 4:0027E, 1997.
We investigated the changes in PGHS specific activity, and the levels
and distribution of PGHS-1 and PGHS-2 mRNA in chorion collected at
term before the onset of labor (CS) and following term labor and
delivery (SL). PGHS specific activity and PGHS-2 mRNA abundance was
higher in chorion collected following SL compared to that obtained at
CS (P<0.001); there was no difference in the levels of PGHS-1
mRNA between CS and SL tissues. The increase in PGHS specific
activity at SL was significantly correlated with PGHS-2 mRNA
expression (P<0.05), but not with PGHS-1 mRNA levels. In situ
hybridization indicated the pervasiveness of staining for PGHS-1 mRNA
throughout full thickness membranes did not change with labor onset,
however, a greater number of cells expressed PGHS-2 in SL tissues.
Our results demonstrate a selective increase in PGHS-2 expression and
activity in chorion trophoblasts and mesenchymal cells with term
labor onset. These observations are similar to amnion and imply a
concerted mechanism may exist in the fetal membranes to induce PGHS-2
expression at labor.
Received 1 November 1996; accepted in final form 15 January 1997.
APS Manuscript Number E552-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 19 February 1997