Related Experiment Videos
Presence of immunoreactive endothelin-1 and atrial natriuretic peptide in human pericardial fluid
F Horkay1, I Szokodi, L Selmeci
1Department of Cardiovascular Surgery, Semmelweis University of Medicine, Budapest, Hungary.
Insights
This study found significantly higher concentrations of endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) in human pericardial fluid compared to plasma. Pericardial fluid exhibits the highest ET-1 levels detected to date.
Area of Science:
- Cardiovascular Physiology
- Biochemistry
Background:
- Endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) are key regulators of cardiovascular function.
- Their presence and concentration in human pericardial fluid remain largely uncharacterized.
Purpose of the Study:
- To quantify endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) levels in human pericardial fluid.
- To compare these levels with those in plasma and cardiac tissues.
- To characterize the molecular forms of ET-1 and ANP in pericardial fluid.
Main Methods:
- Radioimmunoassays were used to measure immunoreactive (ir-) ET-1 and ir-ANP.
- High-performance liquid chromatography (HPLC) was employed for molecular characterization.
- Samples were obtained from patients undergoing cardiac surgery (n=16).
Main Results:
- Pericardial fluid ir-ET-1 and ir-ANP levels were significantly higher (36-fold and 4-fold, respectively) than in plasma.
- Atrial tissue showed markedly higher concentrations of ir-ET-1 (17-fold) and ir-ANP (870-fold) than ventricular tissue.
- HPLC confirmed the identity of ir-ET-1 and the majority of ir-ANP in pericardial fluid.
Conclusions:
- This study is the first to demonstrate the presence of ir-ET-1 in human pericardial fluid.
- Human pericardial fluid contains the highest ET-1 concentrations reported.
- The physiological roles of pericardial ET-1 and ANP in cardiac function and coronary tone warrant further investigation.
Abstract:
This study was undertaken to characterize endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) concentrations in human pericardial fluid, blood plasma, right atrial appendage and papillary muscle by use of specific radioimmunoassays. In patients undergoing cardiac surgery (n=16) pericardial fluid mean immunoreactive (ir-) ET-1 and ir-ANP levels were 36-fold and 4-fold higher than corresponding plasma levels, respectively. In high performance liquid chromatography (HPLC) pericardial fluid ir-ET-1 was indistinguishable from human ET-1[1-21] and the majority of pericardial fluid ir-ANP coeluted with human ANP[99-126]. Atrial tissue ir-ET-1 and ir-ANP concentrations were 17-fold and 870-fold higher than in ventricular tissue. Our present study demonstrated for the first time the presence of ir-ET-1 in the pericardial fluid in humans. Human pericardial fluid contained far the highest concentrations of ET-1 among all biological fluids tested thus far. The functions of pericardial fluid ET-1 and ANP on cardiac performance and coronary vascular tone require further investigations.