The tunica mucosa of the urethra (400X)

The tunica mucosa of the urethra is the innermost layer of the urethral wall, and it plays a crucial role in the function of the urethra. The characteristics of the tunica mucosa can vary depending on the specific part of the urethra (male or female) and its location within the urinary system. It is made up of epithelium and the underlaying lamina propria.

The tunica mucosa is lined with a specialized type of epithelial tissue. In males, the epithelium of the urethra changes along its length. In the prostatic urethra as depicted here, the epithelium is typically transitional epithelium, which is a type of epithelium capable of stretching and accommodating changes in urine flow.

In females, the tunica mucosa of the urethra is typically shorter and simpler than in males, as the female urethra is shorter in length. The epithelium in the female urethra is usually stratified squamous or pseudostratified columnar epithelium.