Advertisement

Molecular and histomorphological evaluation of female rats’ urethral tissues after an innovative trauma model of prolonged vaginal distention: immediate, short-term and long-term effects

  • Maria A. T. Bortolini
  • Suellen M. Feitosa
  • Andreisa P. M. Bilhar
  • Gisela G. R. Salerno
  • Edmar Zanoteli
  • Manuel J. Simões
  • Rodrigo A. Castro
Original Article

Abstract

Introduction and hypothesis

An animal model of vaginal distention (VD) was developed to reproduce the acute urethral injury and deficiency underlying stress urinary incontinence (SUI). Data on the chronic effects of urethral trauma and the recovery process are still scarce. We investigated acute, short- and long-term histomorphological and molecular changes in the urethra of rats post 12-h intermittent VD.

Methods

We evaluated the urethra of four groups of female rats (n = 72): control without trauma, 1 h, 7 days and 30 days post VD. We compared the gene and protein expression of the VEGF and NGF growth factors, collagens (COL1a1 and COL3a1), desmin, smooth muscle myosin (MYH11), skeletal muscle myosins (MYH1, MYH2 and MYH3) and cell proliferation marker MKi67. We used real-time RT-qPCR, and immunohistochemistry.

Results

Histology showed urethral damage after VD mainly involving the muscular layers. VEGF, NGF, desmin and MKi67 mRNA were significantly upregulated in the urethras of rats 1-h post VD compared with controls (P < 0.05 for all). By 7 days post trauma, COL1a1, MYH11 and MYH3 genes were overexpressed compared with controls (p < 0.05 for all). The COL3a1 protein level was increased by 2.6 times by day 7, while MYH2 protein was significantly decreased (around two times) from 7 to 30 days post VD compared with controls (p < 0.05 for both).

Conclusions

The 12-h intermittent VD causes chronic alterations in the urethra represented by increased COL3a1 and decreased MYH2 protein levels in the long term. The model can potentially be used to study the mechanisms of urethral injury and recovery as well as the physiopathology of SUI.

Keywords

Urinary incontinence Trauma Urethra Collagen Muscle 

Notes

Acknowledgements

For excellent assistance, the authors are grateful to Eloísa D. Castro, Gabriel A. Alves and Graciele A. Oliveira.

Compliance with ethical standards

Conflicts of interest

None.

Financial support

This research was supported by Fundação de Apoio à Pesquisa do Estado de São Paulo FAPESP (no. 20.254/2011).

References

  1. 1.
    Haylen BT, de Ridder D, Freeman RM, et al. An International Urogynecological Association (IUGA)/International Continence Society (ICS) joint report on the terminology for female pelvic floor dysfunction. Neurourol Urodyn. 2010;29:4–20.PubMedGoogle Scholar
  2. 2.
    Rud T, Andersson KE, Asmussen M, et al. Factors maintaining the intraurethral pressure in women. Investig Urol. 1980;17(4):343–7.Google Scholar
  3. 3.
    Cannon TW, Wojcik EM, Ferguson CL, et al. Effects of vaginal distension on urethral anatomy and function. BJU Int. 2002;90:403–7.CrossRefPubMedGoogle Scholar
  4. 4.
    Phull HS, Pan HQ, Butler RS, et al. Vulnerability of continence structures to injury by simulated childbirth. Am J Physiol Renal Physiol. 2011;301(3):F641–9.CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Huang J, Cheng M, Ding Y, et al. Modified vaginal dilation rat model for postpartum stress urinary incontinence. J Obstet Gynaecol Res. 2013;39(1):256–63.CrossRefPubMedGoogle Scholar
  6. 6.
    Damaser MS, Broxton-King C, Ferguson C, et al. Functional and neuroanatomical effects of vaginal distension and pudendal nerve crush in the female rat. J Urol. 2003;170:1027–31.CrossRefPubMedGoogle Scholar
  7. 7.
    Pan HQ, Kerns JM, Lin DL, et al. Dual simulated childbirth injury delays anatomic recovery. Am J Physiol Renal Physiol. 2009;296:F277–83.CrossRefPubMedGoogle Scholar
  8. 8.
    Prantil RL, Jankowski RJ, Kaiho Y, et al. Ex vivo biomechanical properties of the female urethra in a rat model of birth trauma. Am J Physiol Renal Physiol. 2007;292:F1229–37.CrossRefPubMedGoogle Scholar
  9. 9.
    Hong SH, Piao S, Kim IG, et al. Comparison of three types of stress urinary incontinence rat models: electrocauterization, pudendal denervation and vaginal distension. Urology. 2013;81:465.e1–6.CrossRefGoogle Scholar
  10. 10.
    Rocha MA, Sartori MGF, Simões MJ, et al. The impact of pregnancy and childbirth in the urethra of female rats. Int Urogynecol J. 2007;18:645–51.CrossRefGoogle Scholar
  11. 11.
    Pan HQ, Kerns JM, Lin DL, et al. Increased duration of simulated childbirth injuries results in increased time to recovery. Am J Physiol Regul Integr Comp Physiol. 2007;292(4):R1738–44.CrossRefPubMedPubMedCentralGoogle Scholar
  12. 12.
    Hofer MD, Cheng EY, Bury MI, et al. Analysis of primary urethral wound healing in the rat. Urology. 2014;84(1):246.e1–7.CrossRefGoogle Scholar
  13. 13.
    Sengupta P. The laboratory rat: relating its age with Human’s. Int J Prev Med. 2013;4(6):624–30.PubMedPubMedCentralGoogle Scholar
  14. 14.
    Jiang HH, Damaser MS. Animal models of stress urinary incontinence. Handb Exp Pharmacol. 2011;202:45–67.CrossRefGoogle Scholar
  15. 15.
    Phillips JI, Davies I. The comparative morphology of the bladder and urethra in young and old female C57BL/Icrfat mice. Exp Geront. 1980;15:551–62.CrossRefGoogle Scholar
  16. 16.
    Woo LL, Hijaz A, Kuang M, et al. Over expression of stem cell homing cytokines in urogenital organs following vaginal distention. J Urol. 2007;177:1568–72.CrossRefPubMedGoogle Scholar
  17. 17.
    Lenis AT, Kuang M, Woo LL, et al. Impact of parturition on chemokine homing factor expression in the vaginal distention model of stress urinary incontinence. J Urol. 2013;189:1588–94.CrossRefPubMedGoogle Scholar
  18. 18.
    Birot OJG, Koulmann N, Peinnequin A, et al. Exercise-induced expression of vascular endothelial growth factor mRNA in rat skeletal muscle is dependent on fibre type. J Physiol. 2003;552(1):213–21.CrossRefPubMedPubMedCentralGoogle Scholar
  19. 19.
    Sofroniew MV, Howe CL, Mobley WC. Nerve growth factor signaling, neuroprotection, and neural repair. Annu Rev Neurosci. 2001;24:1217–81.CrossRefPubMedGoogle Scholar
  20. 20.
    Gerdes J, Schwab U, Lemke H, et al. Production of a mouse monoclonal antibody reactive with a human nuclear antigen associated with cell proliferation. Int J Cancer. 1983;31(1):13–20.CrossRefPubMedGoogle Scholar
  21. 21.
    Wood HM, Kuang M, Woo L, et al. Cytokine expression after vaginal distention of different durations in virgin Sprague-Dawley rats. J Urol. 2008;180:753–9.CrossRefPubMedPubMedCentralGoogle Scholar
  22. 22.
    Huard J, Li Y, Fu FH. Muscle injuries and repair: current trends in research. J Bone Joint Surg Am. 2002;84-A(5):822–32.CrossRefPubMedGoogle Scholar
  23. 23.
    Bornemann A, Schmalbruch H. Desmin and vimentin in regenerating muscles. Muscle Nerve. 1992;15:14–20.CrossRefPubMedGoogle Scholar
  24. 24.
    Beamish JA, He P, Kottke-Marchant K, et al. Molecular regulation of contractile smooth muscle cell phenotype: implications for vascular tissue engineering. Tissue Eng Part B Rev. 2010;16:467–91.CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    Schiaffino S, Rossi AC, Smerdu V, et al. Developmental myosins: expression patterns and functional significance. Skelet Muscle. 2015;5:22.CrossRefPubMedPubMedCentralGoogle Scholar
  26. 26.
    Birk DE, Fitch JM, Babiarz JP, et al. Collagen fibrillogenesis in vitro: interaction of types I and V collagen regulates fibril diameter. J Cell Sci. 1990;95:649–57.PubMedGoogle Scholar
  27. 27.
    Wynn TA. Cellular and molecular mechanisms of fibrosis. J Pathol. 2008;214(2):199–210.CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© The International Urogynecological Association 2018

Authors and Affiliations

  • Maria A. T. Bortolini
    • 1
  • Suellen M. Feitosa
    • 1
  • Andreisa P. M. Bilhar
    • 1
  • Gisela G. R. Salerno
    • 1
  • Edmar Zanoteli
    • 2
  • Manuel J. Simões
    • 1
  • Rodrigo A. Castro
    • 1
  1. 1.Sector of Urogynecology and Vaginal Surgery, Department of GynecologyFederal University of São PauloSão PauloBrazil
  2. 2.Department of Neurology, Faculty of MedicineUniversity of São PauloSão PauloBrazil

Personalised recommendations