Cardiovascular effects of native and non-native urotensin II and urotensin II-related peptide on rat and salmon hearts.
Urotensin II (UII) was first discovered in the urophyses of goby fish and later identified in mammals, while urotensin II-related peptide (URP) was recently isolated from rat brain. We studied the effects of UII on isolated heart preparations of Chinook salmon and Sprague-Dawley rats. Native rat UII caused potent and sustained, dose-dependent dilation of the coronary arteries in the rat, whereas non-native UII (human and trout UII) showed attenuated vasodilation. Rat URP dilated rat coronary arteries, with 10-fold less potency compared with rUII. In salmon, native trout UII caused sustained dilation of the coronary arteries, while rat UII and URP caused significant constriction. Nomega-nitro-(l)-arginine methyl (l-NAME) and indomethacin significantly attenuated the URP and rat UII-induced vasodilation in the rat heart. We conclude that UII is a coronary vasodilator, an action that is species form specific. We also provide the first evidence for cardiac actions of URP, possibly via mechanisms common with UII.
Prosser
H C G
HC
School of Biological Sciences, University of Canterbury, Christchurch, New Zealand. hcp17@student.canterbury.ac.nz
Leprince
J
J
Vaudry
H
H
Richards
A M
AM
Forster
M E
ME
Pemberton
C J
CJ
D000818:Animals; D003331:Coronary Vessels / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D036361:Peptide Hormones / Q000037:antagonists & inhibitors / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012474:Salmon; D014579:Urotensins / Q000037:antagonists & inhibitors / Q000502:physiology*
D036361:Peptide Hormones; D014579:Urotensins; C479081:urotensin II-related peptide, rat; C029677:urotensin II