From the Research
Natriuretic Peptide (NP) Response to Hypotension
- Natriuretic peptides, including atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), are released in response to atrial and ventricular stretch, respectively, and cause vasorelaxation, inhibition of aldosterone secretion, and inhibition of renin secretion in the kidney 1.
- ANP, acting through natriuretic peptide receptor 1 (NPR1), provokes hypotension, which is thought to be due to ANP inducing vasodilation via NPR1 in the vasculature 2.
- The physiologic effects of C-type natriuretic peptide (CNP) are different from those of ANP and BNP, with CNP having a hypotensive effect but no significant diuretic or natriuretic actions 1.
Effect of Hypotension on Natriuretic Peptide Levels
- Controlled hypotension decreases the release of natriuretic peptides in cardiovascular healthy patients, which may be contributed to by changes in cardiac filling pressure due to lower systemic resistance and diminished perfusion pressure 3.
- In patients undergoing endonasal sinus surgery, controlled hypotension using esmolol or sodium nitroprusside resulted in significantly lower concentrations of atrial and brain natriuretic peptide compared to controls 3.
- However, in certain disease states, such as congestive heart failure (CHF), systemic hypertension, and acute myocardial infarction, increased blood levels of natriuretic peptides have been found, suggesting a role in the pathophysiology of those diseases 1, 4.
Regulation of Natriuretic Peptide Levels
- The natriuretic peptides have been used in the treatment of disease, with the most experience with intravenous BNP in the treatment of CHF 1.
- Another pharmacologic approach being used is the inhibition of natriuretic peptide metabolism by neutral endopeptidase (NEP) inhibitor drugs, which are currently being investigated as treatments for CHF and systemic hypertension 1.
- Reversible pegylation of ANP has been shown to prolong the hypotensive effect of ANP, making it a potential candidate for development into an antihypertensive drug 5.