Possible mechanisms involved in the natriuretic response to atrial natriuretic factor (ANF) and proANF 31-67 in the rat.
1. The present study was conducted to compare the mechanisms involved in the natriuretic response to atrial natriuretic factor (ANF) and proANF 31-67. The peptides were infused intravenously into anaesthetized rats at 10 pmol/min for 40 min. 2. Only ANF produced a significant decrease in arterial pressure; the maximum decrease was 11 mmHg (P < 0.05). 3. Both peptides produced significant increases in sodium excretion (P < 0.05) but only ANF increased the cyclic GMP (cGMP) excretion rate (P < 0.01) and neither peptide had a significant effect on plasma renin activity or glomerular filtration rate (GFR). ProANF 31-67 did not increase the plasma levels of ANF. 4. These results demonstrate that both ANF and proANF 31-67 have natriuretic effects via a tubular mechanism and suggest that the natriuretic effects of ANF are mediated by cGMP while the excretion, changes in GFR or a reduction in renin secretion.
Dietz
J R
JR
Department of Physiology and Biophysics, University of South Florida College of Medicine, Tampa, Florida 33612.
Vesely
D L
DL
Nazian
S J
SJ
D000704:Analysis of Variance; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D003404:Creatinine / Q000097:blood / Q000652:urine; D003429:Cross Reactions; D006152:Cyclic GMP / Q000652:urine; D004573:Electrolytes / Q000652:urine; D005919:Glomerular Filtration Rate / Q000187:drug effects; D007262:Infusions, Intravenous; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D010446:Peptide Fragments / Q000008:administration & dosage / Q000494:pharmacology*; D011498:Protein Precursors / Q000008:administration & dosage / Q000494:pharmacology*; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D012083:Renin / Q000097:blood
D004573:Electrolytes; D010446:Peptide Fragments; D011498:Protein Precursors; C054548:atrial natriuretic factor prohormone (31-67); C472610:atrial natriuretic peptide, rat; D009320:Atrial Natriuretic Factor; D003404:Creatinine; D012083:Renin; D006152:Cyclic GMP