Enhanced bladder capacity and reduced prostaglandin E2-mediated bladder hyperactivity in EP3 receptor knockout mice

Area of Science:

• Urology
• Pharmacology
• Molecular Biology

Background:

• Nonsteroidal anti-inflammatory drugs targeting prostaglandin E2 (PGE2) production are effective for urinary bladder overactivity.
• The specific role of the PGE2 receptor, EP3, in bladder function remains unclear.

Purpose of the Study:

• To investigate the functional role of the EP3 receptor in urinary bladder function and overactivity.
• To determine the effect of EP3 receptor knockout on bladder capacity and response to EP3 stimulation.

Main Methods:

• Conscious, freely moving cystometry was performed on EP3 receptor knockout (KO) and wild-type (WT) mice.
• Bladder capacity was measured under control conditions and after infusion of the EP3 agonist GR63799X or PGE2.

Main Results:

• EP3 KO mice exhibited significantly enhanced bladder capacity (approximately 185% of WT) compared to WT mice.
• Infusion of the EP3 agonist GR63799X reduced bladder capacity in WT mice but not in EP3 KO mice.
• PGE2 infusion induced bladder overactivity in WT mice, an effect significantly blunted in EP3 KO mice.

Conclusions:

• The EP3 receptor plays a functional role in normal urinary bladder function.
• EP3 receptor signaling contributes to bladder overactivity, particularly in conditions with elevated PGE2 levels.
• Targeting the EP3 receptor may offer a therapeutic strategy for overactive bladder.