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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Delivery, Obstetric, Female, Mice, Mice, Inbred C57BL, Muscle, Smooth, Urethra, Urinary Incontinence, Stress.
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Does extraordinary muscular structure lead to urethral injury after vaginal delivery in animal study? Context: The aim of this study is to explore causality of birth trauma after vaginal delivery and anatomical findings. A total of 28 virgin mice were studied. Treatment groups received vaginal distention. Specimens were collected and subjected to the following fluorescence stains: progenitor cell (c-kit), smooth muscle (SMA), fibroblast (vimentin), and skeleton muscle (Masson's trichrome). Confocal microscopy was used to screen all of the urogenital tissue to localize the stained cells. Fibroblasts were spread all over perivaginal and urethral surroundings. Progenitor cells appeared at urethral-vagina intersection and urethral circle. They were noticeable only within smooth muscle layer. Two extraordinary skeleton muscle bands appeared on the urethra bilaterally.
assistant
Our study demonstrates existence of muscle bands at the bilateral urethra. They can limit the mobility of urethra during vaginal delivery and thereby cause urethra injury. Progenitor cells are located only in the smooth muscle of the urethral circle. Final Decision: yes