Prostaglandin E2-regulated cervical ripening: analysis of proteoglycan expression in the rat cervix.
OBJECTIVE
Prostaglandins reduce cervical resistance by reorganizing collagen fibrils. Proteoglycans are involved in collagen fibril organization and structure. We evaluated the changes in proteoglycan composition induced by prostaglandin E(2) (PGE(2)).


METHODS
Prostaglandins were administered intravaginally to induce cervical ripening in timed pregnant Sprague-Dawley rats. Changes in proteoglycan messenger ribonucleic acid (mRNA) expression were measured using reverse transcription (RT-PCR) for core protein. Fluorophore assisted carbohydrate gel electrophoresis (FACE) was used to evaluate proteoglycan glycosaminoglycan composition along with size exclusion high-performance liquid chromatography (HPLC).


RESULTS
No change in core protein mRNA expression was detected after PGE(2) treatment. Total glycosaminoglycan (GAG) decreased more than 20% after PGE(2) (P = .02). FACE demonstrated a shift in disaccharide subunit composition after PGE(2), with a decrease in 4-sulfated disaccharides (P = .02). HPLC confirmed a decrease in total GAG (P = .04).


CONCLUSIONS
Although there was no change in core protein mRNA expression, alterations in GAG composition was detected after PGE(2). The decrease in sulfated GAG could decrease electrostatic interactions that would weaken interfibrillar interactions. These findings would be consistent with a decline in cervical resistance.
Ji
Huiling
H
Section of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Women and Infants' Hospital of Rhode Island, and Warren Alpert Medical School at Brown University, Providence, RI, USA.
Dailey
Tanya L
TL
Long
Vit
V
Chien
Edward K
EK
D000282:Administration, Intravaginal; D000818:Animals; D001665:Binding Sites / Q000502:physiology; D020070:Cervical Ripening / Q000187:drug effects* / Q000502:physiology; D002584:Cervix Uteri / Q000187:drug effects / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D015232:Dinoprostone / Q000494:pharmacology*; D005260:Female; D014453:Glucuronosyltransferase / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D000076002:Hyaluronan Synthases; D007150:Immunohistochemistry; D016612:Paraffin Embedding; D011247:Pregnancy; D011509:Proteoglycans / Q000737:chemistry / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D018078:Receptors, Prostaglandin E; D020133:Reverse Transcriptase Polymerase Chain Reaction
D006025:Glycosaminoglycans; D011509:Proteoglycans; D012333:RNA, Messenger; D018078:Receptors, Prostaglandin E; D014453:Glucuronosyltransferase; C491097:Has2 protein, rat; D000076002:Hyaluronan Synthases; D015232:Dinoprostone