Concentration of non-steroidal anti-inflammatory drugs in the pelvic floor muscles: an experimental comparative rat model.

PURPOSE: The aim of this study is to explore non-steroid anti-inflammation drugs (NSAIDs) potency for pelvic floor muscle pain by measuring local concentration in a rat model. MATERIALS AND METHODS: We used nine NSAIDs, including nabumetone, naproxen, ibuprofen, meloxicam, piroxicam, diclofenac potassium, etodolac, indomethacin, and sulindac, and 9 groups of female Wister rats. Each group of rats was fed with one kind of NSAID (2 mg/mL) for three consecutive days. Thereafter, one mL of blood and one gram of pelvic floor muscle were taken to measure drug pharmacokinetics, including partition coefficient, lipophilicity, elimination of half-life (T1/2) and muscle/plasma converting ratio (Css, muscle/Css, plasma). RESULTS: Diclofenac potassium had the lowest T1/2 and the highest mean Css, muscle/Css, plasma (1.9 hours and 0.85±0.53, respectively). The mean Css, muscle/Css, plasma of sulindac, naproxen and ibuprofen were lower than other experimental NSAIDs. CONCLUSION: Diclofenac potassium had the highest disposition in pelvic floor muscle in a rat model. The finding implies that diclofenac potassium might be the choice for pain relief in pelvic muscle.

Extraordinary muscular structure leads to urethral injury after vaginal delivery in animal study.

INTRODUCTION AND HYPOTHESIS: The aim of this study is to explore causality of birth trauma after vaginal delivery and anatomical findings. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.