Social stress in mice induces voiding dysfunction and bladder wall remodeling.

Area of Science:

• Urology
• Neuroscience
• Molecular Biology

Background:

• Social stress is anecdotally linked to altered urinary voiding patterns in rodents.
• Previous research characterized urodynamic and central changes in a rat model of social defeat.

Purpose of the Study:

• To characterize social stress-induced voiding phenotype in mice.
• To investigate molecular mechanisms underlying bladder wall remodeling due to social stress.
• To explore the relevance to human dysfunctional voiding with psychological components.

Main Methods:

• FVB mice were subjected to a 4-week social stress paradigm or control manipulation.
• In vivo cystometry was performed to assess urodynamic parameters.
• Bladder tissue was analyzed for nuclear expression of MEF-2 and NFAT, myosin heavy chain B isoform mRNA, and BrdU uptake.

Main Results:

• Social stress induced altered urinary voiding patterns, suggesting urinary retention and increased bladder mass.
• Cystometry showed an increased volume at micturition without changes in voiding pressure.
• Increased nuclear expression of MEF-2 and NFAT, elevated myosin heavy chain B isoform mRNA, and increased BrdU uptake were observed in stressed bladders.

Conclusions:

• Social stress leads to urinary retention and subsequent bladder wall remodeling.
• Molecular mechanisms involve shifts in transcription factors, myosin heavy chain isoform expression, and increased DNA synthesis.
• This rodent model provides insights into the mechanisms and potential treatments for human dysfunctional voiding.