Secretory component: a potential regulator of endometrial-decidual prostaglandin production in early human pregnancy.
OBJECTIVE
We sought to investigate the production of secretory component, an inhibitor of phospholipase A(2), and prostaglandins by human endometrium-decidua.


METHODS
The production of secretory component and prostaglandins by explants and dispersed glandular and stromal cells of secretory endometrium and first-trimester and term decidua were measured by enzyme-linked immunosorbent assay and radioimmunoassay, respectively.


RESULTS
Explants of first-trimester decidua produced significantly more secretory component and less prostaglandins than secretory endometrium. Immunohistochemical studies localized secretory component to epithelial glandular cells. At term, when fewer glandular cells are present, both secretory component and prostaglandin production were low. Exposure of first-trimester decidua to progesterone significantly increased secretory component production.


CONCLUSIONS
Secretory component and prostaglandins localize primarily to epithelial glandular cells in endometrium-decidua, and their production appears to be inversely correlated. The increase in secretory component by first-trimester decidua after progesterone stimulation may account for the down-regulation of endometrial prostaglandin synthesis after implantation, a process thought to be necessary for pregnancy success.
Nuffield Department of Obstetrics and Gynaecology, John Radcliffe Hospital, Oxford University,
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Norwitz
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Wilson
D000293:Adolescent; D000328:Adult; D046508:Culture Techniques; D003656:Decidua / Q000737:chemistry / Q000378:metabolism*; D015237:Dinoprost / Q000031:analogs & derivatives / Q000096:biosynthesis; D015232:Dinoprostone / Q000031:analogs & derivatives / Q000096:biosynthesis; D004717:Endometrium / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis / Q000096:biosynthesis; D007150:Immunohistochemistry; D008875:Middle Aged; D011247:Pregnancy; D015230:Prostaglandin D2 / Q000096:biosynthesis; D011453:Prostaglandins / Q000096:biosynthesis*; D012635:Secretory Component / Q000032:analysis / Q000502:physiology*; D017154:Stromal Cells / Q000378:metabolism
D007070:Immunoglobulin A; D011453:Prostaglandins; D012635:Secretory Component; C008228:15-keto-13,14-dihydroprostaglandin F2alpha; C025087:15-keto-13,14-dihydroprostaglandin E2; D015237:Dinoprost; D015232:Dinoprostone; D015230:Prostaglandin D2