Effects of brain natriuretic peptide-45, a circulating form of rat brain natriuretic peptide, in spontaneously hypertensive rats.
Rat brain natriuretic peptide-45 (rat BNP-45) has recently been isolated from rat heart and shown to be a circulating form of rat BNP. We investigated the effects of rat BNP-45 in anesthetized spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) and compared them with those of rat alpha-atrial natriuretic peptide (alpha-ANP). BNP-45 was a potent natriuretic and hypotensive agent in both strains. The effects were comparable with those of alpha-ANP and were far greater than those of porcine BNP-26 reported previously. In SHR blood pressure decreased more than in WKY following injection of the highest dose (2.0 nmol/kg) of BNP-45 or alpha-ANP. However, WKY were more susceptible than SHR to BNP-45 for diuresis, natriuresis and urinary cGMP excretion. Moreover, a high dose of BNP-45 led to a prolonged lowering of blood pressure and urinary cGMP excretion compared to alpha-ANP, and these features were prominent in WKY. BNP-45 disappeared more slowly than alpha-ANP when the two peptide (2.0 micrograms) were injected i.v. in WKY. Thus, rat BNP-45 and alpha-ANP had comparable hypotensive and natriuretic potency; however, the action and plasma half-life of rat BNP-45 were more prolonged.
Kita
T
T
First Department of Internal Medicine, Miyazaki Medical College, Japan.
Kida
O
O
Yokota
N
N
Eto
T
T
Minamino
N
N
Kangawa
K
K
Matsuo
H
H
Tanaka
K
K
D000595:Amino Acid Sequence; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D006152:Cyclic GMP / Q000652:urine; D004232:Diuretics / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008969:Molecular Sequence Data; D020097:Natriuretic Peptide, Brain; D009419:Nerve Tissue Proteins / Q000493:pharmacokinetics / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D014563:Urodynamics / Q000187:drug effects
D000959:Antihypertensive Agents; D004232:Diuretics; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D020097:Natriuretic Peptide, Brain; C073021:brain natriuretic peptide-45; D009320:Atrial Natriuretic Factor; D006152:Cyclic GMP