The trigone of the urinary bladder is a triangular-shaped region located within the urinary bladder. It is characterized by its smooth and thin lining, consisting of specialized mucosal cells, and serves as an important anatomical landmark in the bladder.
The trigone is located at the base of the bladder, between the two ureteral openings and the urethral opening. It is outlined by three prominent structures: the two ureteral orifices, which are the openings through which urine flows from the kidneys into the bladder, and the internal urethral orifice, which is the opening through which urine exits the bladder.
The trigone plays a significant role in the maintenance of urinary function. Due to its specialized lining, the trigone is relatively resistant to stretching, providing stability to the bladder during filling and emptying. It also acts as a smooth surface that prevents urine stagnation and helps ensure effective emptying.
Moreover, the trigone has been associated with the sensation of fullness and the urge to urinate, as it contains a high concentration of sensory nerve endings. These nerve endings transmit signals to the brain, providing the sensation of bladder distention, which triggers the desire to urinate.
In summary, the trigone of the urinary bladder refers to a triangular region located at the base of the bladder, outlined by the two ureteral orifices and the internal urethral orifice. It has a specialized lining, plays a role in bladder stability and emptying, and contains sensory nerve endings that contribute to the sensation of fullness and urination.
