Normalization of up-regulated cardiac imidazoline I(1)-receptors and natriuretic peptides by chronic treatment with moxonidine in spontaneously hypertensive rats.
The effect of treatment with moxonidine (120 mg/kg/h sc, 4 weeks) on cardiac I(1)-receptors and natriuretic peptide synthesis was evaluated in spontaneously hypertensive rats (SHR). I(1)-receptor protein (85 kD) was up-regulated in SHR atria, and normalized in right and left atria by moxonidine. Similarly, moxonidine normalized atrial and ventricular atrial natriuretic peptide messenger RNA (mRNA) and brain natriuretic peptide mRNA. This study shows that cardiac I(1)-receptors are functional, being regulated by hypertension and by chronic exposure to agonist, and that cardiac natriuretic peptides may be regulated by I(1)-receptor-mediated mechanisms.
El-Ayoubi
R
R
CHUM-Research Center, Université de Montréal, Montreal, Quebec, Canada.
Menaouar
A
A
Gutkowska
J
J
Mukaddam-Daher
S
S
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006325:Heart Atria / Q000378:metabolism; D007093:Imidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D054755:Imidazoline Receptors; D020097:Natriuretic Peptide, Brain / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011918:Rats, Inbred SHR; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000378:metabolism*; D015854:Up-Regulation; D016276:Ventricular Function
D007093:Imidazoles; D054755:Imidazoline Receptors; D011955:Receptors, Drug; C410887:imidazoline I1 receptors; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor; C043482:moxonidine