Mechanical ventilation with positive end-expiratory pressure decreases the circulating concentrations of the N-terminus and C-terminus of the atrial natriuretic factor prohormone.
Mechanical ventilation with positive end-expiratory pressure (PEEP) decreases urine output and urinary sodium excretion. The influence of PEEP during controlled mechanical ventilation on the circulating concentrations of the N-terminus and C-terminus of the atrial natriuretic factor (ANF) prohormone which both contain natriuretic and diuretic peptides was investigated in 7 patients with acute respiratory failure. The 98 amino acid (aa) N-terminus, the midportion of the N-terminus consisting of aa 31-67 of the 126 aa ANF prohormone (i.e., pro ANF 31-67) and the C-terminus (aa 99-126; ANF) were found to be significantly (p less than 0.05; ANOVA) elevated compared to 54 healthy volunteers during acute respiratory failure prior to institution of PEEP. With institution of 10 cm of H2O of PEEP all 7 patients had a significant (p less than 0.05) decrease in the circulating concentrations of pro ANFs 1-98, 31-67 and ANF. These findings suggest that the increased thoracic pressure secondary to PEEP which reduces venous return and lowers atrial filling pressure results in a decreased release of the N-terminus and C-terminus of the ANF prohormone. This decrease in the N-terminus and C-terminus of the ANF prohormone appears to represent a physiologic mechanism for restoration of intravascular volume, secondary to decreased sodium excretion.
Vesely
D L
DL
Department of Internal Medicine, University of South Florida for Health Sciences, James A. Haley Veterans Administration Hospital, Tampa.
Salmon
J S
JS
D000208:Acute Disease; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009318:Natriuresis / Q000502:physiology; D010446:Peptide Fragments / Q000097:blood*; D011175:Positive-Pressure Respiration; D011498:Protein Precursors / Q000097:blood*; D012121:Respiration, Artificial; D012131:Respiratory Insufficiency / Q000097:blood* / Q000628:therapy
D010446:Peptide Fragments; D011498:Protein Precursors; C054548:atrial natriuretic factor prohormone (31-67); C055659:atrial natriuretic factor prohormone (1-98); D009320:Atrial Natriuretic Factor