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Ultrastructure of the trigone and its functional implications
1Department of Pathology, Upstate Medical University, State University of New York, Syracuse, NY, USA. john@uro.usz.ch
Urologia Internationalis
|December 13, 2001
Summary
The trigonal muscle shows no structural changes in voiding dysfunction, unlike the detrusor. Its function relies on electrical coupling for normal micturition and ureter support.
Area of Science:
- Urology
- Cell Biology
- Anatomy
Background:
- The trigonal muscle, or superficial trigone, plays a role in bladder function.
- Understanding its ultrastructure is crucial for diagnosing voiding dysfunction.
Purpose of the Study:
- To investigate the trigonal muscle's ultrastructure.
- To correlate its structure with normal function.
- To identify changes associated with voiding dysfunction.
Main Methods:
- Electron microscopy of trigonal biopsies from 20 men (10 obstructed, 10 unobstructed).
- Urodynamic evaluation to assess bladder outlet obstruction.
- Independent evaluation of biopsies by two examiners.
Main Results:
- Trigonal muscle has smaller bundles, less collagen, and more elastic tissue than detrusor.
- Muscle cells exhibit electrical coupling (close appositions) rather than mechanical coupling (intermediate junctions).
- No trigonal structural changes were observed that are typically associated with voiding dysfunction or detrusor changes.
Conclusions:
- The trigonal muscle does not structurally alter in response to voiding dysfunction.
- Its function relies on electrical coupling and it supports ureter anchoring during micturition.
- Sensory neuroterminals in the trigone may influence micturition reflexes and urge perception.
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