HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 295/4/R1351    most recent 90447.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Rahn, D. D. Articles by Word, R. A. Search for Related Content PubMed PubMed Citation Articles by Rahn, D. D. Articles by Word, R. A.

UROGENITAL PHYSIOLOGY

Effect of vaginal distention on elastic fiber synthesis and matrix degradation in the vaginal wall: potential role in the pathogenesis of pelvic organ prolapse

University of Texas Southwestern Medical Center, Dallas, Texas

Submitted 22 May 2008 ; accepted in final form 14 July 2008

Matrix metalloprotease (MMP) activity is increased in the postpartum vagina of wild-type (WT) animals. This degradative activity is also accompanied by a burst in elastic fiber synthesis and assembly. The mechanisms that precipitate these changes are unclear. The goals of this study were to determine how vaginal distention (such as in parturition) affects elastic fiber homeostasis in the vaginal wall and the potential significance of these changes in the pathogenesis of pelvic organ prolapse. Vaginal distention with a balloon simulating parturition resulted in increased MMP-2 and MMP-9 activity in the vaginal wall of nonpregnant and pregnant animals. This was accompanied by visible fragmented and disrupted elastic fibers in the vaginal wall. In nonpregnant animals, the abundant amounts of tropoelastin and fibulin-5 in the vagina were not increased further by distention. In contrast, in pregnant animals, the suppressed levels of both proteins were increased 3-fold after vaginal distention. Distention performed in fibulin-5-deficient (Fbln5^–/–) mice with defective elastic fiber synthesis and assembly induced accelerated pelvic organ prolapse, which never recovered. We conclude that, in pregnant mice, vaginal distention results in increased protease activity in the vaginal wall but also increased synthesis of proteins important for elastic fiber assembly. Distention may thereby contribute to the burst of elastic fiber synthesis in the postpartum vagina. The finding that distention results in accelerated pelvic organ prolapse in Fbln5^–/– animals, but not in WT, indicates that elastic fiber synthesis is crucial for recovery of the vaginal wall from distention-induced increases in vaginal protease activity.

childbirth trauma; MMP9; protease; pregnancy

This article has been cited by other articles:

				C. K. Wieslander, D. D. Rahn, D. D. McIntire, J. F. Acevedo, P. G. Drewes, H. Yanagisawa, and R. A. Word Quantification of Pelvic Organ Prolapse in Mice: Vaginal Protease Activity Precedes Increased MOPQ Scores in Fibulin 5 Knockout Mice Biol Reprod, March 1, 2009; 80(3): 407 - 414. [Abstract] [Full Text] [PDF]