Distribution of rabbit mucosal glycoprotein throughout urinary tract

The mucin layer covering the transitional epithelium of the bladder is thought to be an anti-adherence substance for bacteria. We describe the use of an immunoperoxidase staining technique to demonstrate the presence of glycoprotein lining the urothelium of both the upper and lower urinary tracts of the rabbit. Antisera against this glycoprotein (GP1) were raised in Swiss-Webster mice. The genitourinary tracts of male and female NZW rabbits were removed and sequentially treated with mouse anti-GP1 sera, biotin-labelled anti-mouse IgG, and an avidin-biotinylated horseradish peroxidase complex. The results demonstrated that an antigenically similar (or identical) glycoprotein covers the distal renal tubules and urothelium of the renal pelvis, ureters, bladder, and urethra, suggesting that it may function as an antibacterial defense mechanism throughout the urinary tract.