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Updated: Jul 16, 2026
06:36
A Decentralized (Ex Vivo) Murine Bladder Model with the Detrusor Muscle Removed for Direct Access to the Suburothelium during Bladder Filling
Published on: November 28, 2019
Non-neuronal acetylcholine and urinary bladder urothelium
Ann T Hanna-Mitchell1, Jonathan M Beckel, Stephanie Barbadora
1University of Pittsburgh School of Medicine Department of Medicine, Pittsburgh, PA 15261, USA.
Life Sciences
|March 17, 2007
Summary
Urothelial cells in the rat urinary bladder synthesize and release acetylcholine (ACh). This non-neuronal ACh release, distinct from nerve mechanisms, may regulate bladder function via negative feedback.
Area of Science:
- Urology
- Neuroscience
- Cell Biology
Background:
- Non-neuronal acetylcholine (ACh) is implicated in urinary bladder function.
- The specific mechanisms of ACh synthesis and release in urothelial cells remain unclear.
Purpose of the Study:
- To investigate the expression and function of the non-neuronal cholinergic system in cultured rat urothelial cells.
- To elucidate the mechanisms of ACh release from urothelial cells.
Main Methods:
- Cultured rat urothelial cells were analyzed for the expression of cholinergic markers.
- Radioactive choline was used to study ACh synthesis and release.
- Stimulation methods included mechanical (hypotonic Krebs) and chemical (ATP) challenges.
- The role of muscarinic receptors and vesicular transport was examined.
Main Results:
- Urothelial cells express choline transporter (CHT1) and ACh-synthesizing enzymes (ChAT, CarAT).
- Cells lack vesicular ACh transporter (VAChT) but express OCT3, involved in non-neuronal ACh release.
- Mechanical and ATP stimulation evoked release of radioactivity (putative ACh).
- Atropine pretreatment facilitated ACh-induced release, suggesting negative feedback.
- Brefeldin did not inhibit hypotonic-evoked release, indicating non-vesicular release.
Conclusions:
- Rat urothelial cells possess a non-neuronal cholinergic system for ACh synthesis and release.
- Urothelial ACh release mechanisms differ from neuronal vesicular exocytosis.
- Released ACh may regulate urothelial function through autocrine negative feedback.
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