Importance of comparative studies to general understanding of endocrine systems
Our research has embraced fish, reptilian and mammalian models, including Man. Investigations of endocrine control of sodium and water management and more recently calcium homeostasis, integrate molecular, biochemical, cellular and whole organism approaches. In recognition of the high level of conservation of these vital body processes through the vertebrate series, key research questions have been moved back and forth between species. This has brought experience and knowledge from one group to bear on the development of understanding in others and in so doing enhancing our general appreciation of these core homeostatic mechanisms.
This Comparative or Model Hopping approach has paid rich dividends for understanding key biological questions in fish. It has also led to the discovery of novel aspects of mammalian ion- and osmo-regulatory physiology and provided insights into aspects of major human diseases. Advances in understanding of the hormone, Urotensin II (UII), only recently identified in mammals, illustrates this well. We are now aware that the ligand and UII receptor (UT) structures are highly conserved from fish to mammals. A long term established linkage of UII with fish osmoregulatory physiology drove our investigation of possible renal actions of UII in mammals. The endogenous peptide appears to have profound tonal influence to restrict renal excretion of water and electrolytes in rat models, which may be related to the growing awareness of UII association with human cardiovascular and renal disorders, including hypertension.