Inhibition of polyamine synthesis impairs the secretion of atrial natriuretic peptide.
The aim of the present study was to evaluate in vivo the role of polyamines in the secretion of atrial natriuretic peptide (ANP). alpha-Difluoromethylornithine (DFMO) which inhibits ornithine decarboxylase activity and polyamine synthesis was given in drinking water and through intraperitoneal administration to Sprague-Dawley rats. Carotid artery was cannulated for collection of blood samples and measurement of blood pressure following the administration of arginine-vasopressin (AVP). Analysis of polyamines in cardiac tissue indicated that DFMO treatment decreased contents of putrescine and spermidine in cardiac tissue by 80% and 48%, respectively. Quantitation of ANP in plasma by radioimmunoassay indicated that both basal and stimulated levels of ANP in DFMO-treated animals were 21.5% and 50% of those in control rats. The administration of putrescine restored the levels of basal and AVP-stimulated levels of ANP in plasma which confirmed that DFMO effect on ANP secretion occurred specifically through the polyamine pathway.
Tipnis
U R
UR
Department of Pathology, University of Texas Medical Branch, Galveston 77550.
Boor
P J
PJ
D000818:Animals; D001127:Arginine Vasopressin / Q000008:administration & dosage / Q000494:pharmacology*; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects; D000518:Eflornithine / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D065108:Ornithine Decarboxylase Inhibitors; D011073:Polyamines / Q000378:metabolism*; D011700:Putrescine / Q000378:metabolism / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013095:Spermidine / Q000378:metabolism
D065108:Ornithine Decarboxylase Inhibitors; D011073:Polyamines; D001127:Arginine Vasopressin; D009320:Atrial Natriuretic Factor; D013095:Spermidine; D011700:Putrescine; D000518:Eflornithine