Bladder Trigone as a Sensory Hub: A Narrative Review

Area of Science:

• Neuroscience
• Urology
• Cell Biology

Background:

• The bladder trigone, a distinct lower urinary tract region, possesses unique sensory innervation.
• Dysregulation of trigonal signaling contributes to lower urinary tract symptoms (LUTS) like urgency and pain.
• The precise structural and functional basis of trigonal sensory signaling remains incompletely understood.

Purpose of the Study:

• To synthesize current evidence on trigonal afferent organization and sensory signaling.
• To integrate anatomical, molecular, and functional data on trigonal sensory pathways.
• To provide a comprehensive perspective on the trigone's role in bladder sensation and dysfunction.

Main Methods:

• Review of anatomical mapping, receptor profiling, and electrophysiological characterization.
• Integration of data on mechanotransduction, purinergic, peptidergic, and TRP signaling.
• Analysis of translational research and functional assays in aging, inflammation, and disease models.

Main Results:

• Identified three principal afferent classes in the trigone with specific molecular markers (P2X3, TRPV1, CGRP, SP, PIEZO1/2, ASICs).
• Observed high expression of PIEZO2, P2RX3, and Nav1.8 in trigeminal dorsal root ganglion neurons.
• Demonstrated that aging, inflammation, and neurotrophic factors drive afferent plasticity underlying abnormal bladder sensation.

Conclusions:

• The bladder trigone acts as a critical sensory hub integrating neuronal, urothelial, and immune signals.
• Understanding trigonal specialization can inform targeted therapies for sensory urgency and bladder dysfunction.
• Early clinical trials with P2X3 antagonists and TRPV1 inhibitors show promise for symptomatic relief.