Substantial detrusor overactivity in conscious spontaneously hypertensive rats with hyperactive behaviour

Area of Science:

• Urology
• Animal Models
• Physiology

Background:

• The spontaneously hypertensive rat (SHR) is a common model for studying detrusor overactivity (DO).
• Hyperactive behavior in SHRs can confound cystometric data interpretation due to abdominal straining (AS).

Purpose of the Study:

• To accurately evaluate true DO in conscious SHRs by differentiating it from AS.
• To highlight the importance of simultaneous intra-abdominal pressure (IAP) and intravesical pressure (IVP) measurements.

Main Methods:

• Simultaneous recording of IVP and IAP in conscious SHRs and Wistar rats.
• Quantification of IVP rises (IVPRs) and differentiation between DO and AS based on IAP changes.

Main Results:

• SHRs exhibited shorter filling phases and more frequent IVPRs compared to Wistar rats.
• DO was present in SHRs, accounting for up to 76% of IVPRs, with the remainder attributed to AS.
• SHRs showed increased AS amplitude but not frequency compared to Wistar rats.

Conclusions:

• Abdominal straining in SHRs can lead to misinterpretation of pressure parameters and false reports of DO.
• Simultaneous registration of IAP and IVP is essential for accurate assessment of DO in conscious SHRs.