Urine Depletion and Bladder Rinsing in Mouse Model: A Catheter-based Procedure to Empty and Wash Murine Urinary Bladder

To empty and wash a mouse's urinary bladder, begin by taking an anesthetized female mouse in the supine position. Next, obtain an appropriately-sized catheter. Lubricate the tip of the catheter to reduce friction and ensure a smooth urethral insertion. Then, slowly and gently insert the lubricated catheter, passing it through the urethral opening, into the bladder.

Upon successful catheterization, the urine begins to drain out of the bladder into the catheter. Now, empty the urine-filled catheter. Using a pipette, add a suitable buffered saline into the outer end of the catheter while its opposite end is within the bladder. To the outer end of the catheter, then attach a syringe. Gently push the syringe to deliver the saline to the bladder.

Now, remove the syringe. Allow the saline, along with the residual urine, to drain out of the bladder through the catheter. Subsequently, vacate the residual urine mixed with saline from the catheter. Repeat the bladder washing with saline twice to ensure complete removal of the urine from the bladder. The prepped mouse is finally ready for further experimental procedures.