International Urology and Nephrology

, Volume 51, Issue 1, pp 61–72 | Cite as

Effect of high-fat diet-induced obesity on the small-conductance Ca2+-activated K+ channel function affecting the contractility of rat detrusor smooth muscle

  • Ning Li
  • Honglin Ding
  • Zizheng Li
  • Yili LiuEmail author
  • Ping Wang
Urology - Original Paper



Obesity usually induces overactive bladder (OAB) associated with detrusor overactivity, which is related to increased contractility of the detrusor smooth muscle (DSM). Small-conductance Ca2+-activated K+ (SK) channels play a constitutive role in the regulation of DSM contractility. However, the role of SK channels in the DSM changes in obesity-related OAB is still unknown. Here, we tested the hypothesis that obesity-related OAB is associated with reduced expression and activity of SK channels in DSM and that SK channels activation is a potential treatment for OAB.


Female Sprague–Dawley rats were fed a normal diet (ND) or a high-fat diet (HFD) and weighed after 12 weeks. Urodynamic studies, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and isometric tension recording were performed.


Increased average body weights and urodynamically demonstrated OAB were observed in HFD rats. qRT-PCR experiments revealed a decrease in the mRNA expression level of SK channel in DSM tissue of the HFD rats. Isometric tension recordings indicated an attenuated relaxation effect of NS309 on the spontaneous phasic and electrical field stimulation-induced contractions that occurred via SK channel activation in HFD DSM strips.


Reduced expression and activity of SK channels in the DSM contribute to obesity-related OAB, indicating that SK channels are a potential therapeutic target for OAB.


SK channel Overactive bladder Detrusor smooth muscle High-fat diet Obesity 



Supported by the LNCCC LNCCC-D16-2015 grant to Ning Li; the National Science Foundation of Liaoning Province 2015020493 grant to Ning Li.

Compliance with ethical standards

Conflict of interest

All authors declare no conflict of interest.

Ethical approval

All applicable International, National, and Institutional Guidelines for the care and use of animals were followed.


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Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  • Ning Li
    • 1
  • Honglin Ding
    • 1
    • 2
  • Zizheng Li
    • 1
  • Yili Liu
    • 1
    Email author
  • Ping Wang
    • 1
  1. 1.Department of Urology, Fourth Affiliated HospitalChina Medical UniversityShenyangChina
  2. 2.Department of Urology, Affiliated HospitalChifeng UniversityChifengChina

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