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A role for epithelium-derived 6-nitrodopamine on human ureter contractility
Wilmar Azal Neto1, Denis Lima Oliveira2, José Britto-Júnior2
1Department of Surgery, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil.
British Journal of Pharmacology
|January 7, 2026
Summary
Human ureters release 6-nitrodopamine (6-ND), a novel catecholamine that influences ureter smooth muscle contractility and modulates ureteral peristalsis.
Area of Science:
- Urology
- Pharmacology
- Physiology
Background:
- The human ureter's physiological functions are not fully understood.
- Novel signaling molecules may play a role in ureteral contractility.
Purpose of the Study:
- To investigate the basal release of 6-nitrodopamine (6-ND) from human isolated ureters.
- To determine the role of 6-ND in ureter smooth muscle contractility.
Main Methods:
- Human ureter segments from organ donors were used.
- Basal 6-ND release was measured using liquid chromatography-tandem mass spectrometry.
- Ureter ring contractions were measured isometrically, and tissue expression of tyrosine hydroxylase (TH) and eNOS was analyzed.
Main Results:
- Basal 6-ND release was higher in intact ureter samples compared to denuded ones.
- 6-ND induced concentration-dependent contractions and potentiated noradrenaline and adrenaline-induced contractions.
- TH and eNOS were expressed in the ureteral epithelium.
Conclusions:
- 6-ND is released by the human ureter.
- This novel catecholamine modulates ureter smooth muscle contractility.
- 6-ND offers new insights into the mechanisms of ureteral peristalsis.
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