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Urotensin II: lessons from comparative studies for general endocrinology.
W Lu1, A E S Abdel-Razik, N Ashton
1Integrative Biology Division, Faculty of Life Sciences, University of Manchester, 3.614 Stopford Building, Oxford Road, Manchester M13 9PT, UK.
General and Comparative Endocrinology
|April 29, 2008
Summary
Comparative studies reveal Urotensin II (UII) and its receptor (UT) are highly conserved across vertebrates. Endogenous UII influences kidney function, impacting water and electrolyte excretion, with implications for human cardiovascular and renal health.
Area of Science:
- Comparative endocrinology
- Physiology
- Genomics
Background:
- Urotensin II (UII) and its receptor (UT) show high structural conservation across vertebrates, from fish to mammals.
- Genome analyses have advanced understanding of UII and UT structures and functions.
- UII's known role in fish osmoregulation prompted investigation into its mammalian renal actions.
Purpose of the Study:
- To explore the conserved functions of the Urotensin II system across vertebrates.
- To investigate the renal actions of Urotensin II in mammals.
- To compare Urotensin II receptor sequences between fish and mammals.
Main Methods:
- Review of genome analyses and UII/UT structure.
- Administration of UT receptor antagonist (urantide) in anesthetized rats.
- Comparison of mammalian UT sequences with newly sequenced fish UT.
Main Results:
- Endogenous UII tonically influences renal excretion of water and electrolytes in mammals.
- UII blockade lowers renal filtration rates and excretion of water and ions.
- UT expression in fish osmoregulatory tissues shows plasticity in response to physiological challenges.
Conclusions:
- The Urotensin II system is a highly conserved endocrine and paracrine system across vertebrates.
- Comparative approaches enhance understanding of UII's novel actions and physiological roles.
- UII's renal effects in mammals may link to human cardiovascular and renal disorders.
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