Related Experiment Video
Updated: Jul 6, 2026
Isolation of Atrial Myocytes from Adult Mice
Published on: July 25, 2019
Priming of polymorphonuclear neutrophils by atrial natriuretic peptide in vitro
C J Wiedermann1, M Niedermühlbichler, H Braunsteiner
1Department of Internal Medicine, Faculty of Medicine, University of Innsbruck, Austria.
Abstract:
In ischemia-reflow states of coronary artery disease, the activation of PMN precedes the initiation of tissue damage. Release of atrial natriuretic peptide (ANP) from myocytes occurs within minutes after the onset of myocardial ischemia, which suggests a possible role of ANP in PMN activation. To investigate this possibility, we tested the effects of ANP on functions of PMN in vitro. ANP is a potent signal for priming the PMN respiration burst to secrete superoxide anion. Phorbol 12-myristate 13-acetate, opsonized zymosan, or FMLP could all be used as triggering stimuli to demonstrate the priming of PMN activation by ANP. Only ANP fragments 1-28 and 7-28 enhanced respiration burst activity but identical preparations of ANP fragments 13-18 or 1-11 failed to do so. This structure-activity relationship is typical of receptors for ANP found in other tissues. In addition, ANP stimulated the release of beta-glucuronidase From PMN triggered by FMLP. The observed inhibition by ANP of FMLP-stimulated chemotaxis of PMN may be due to their enhanced adhesiveness. These data show that a classic cardiac hormone is involved in regulating important functional activities of PMN. These data support the possibility that ANP could act as a preinflammatory substance in ischemia-reperfusion states and myocardial necrosis.
Insights
Atrial natriuretic peptide (ANP) primes neutrophils (PMN) for activation during cardiac ischemia-reperfusion. ANP enhances PMN functions like superoxide anion and beta-glucuronidase release, suggesting a preinflammatory role.
Area of Science:
- Cardiology
- Immunology
- Biochemistry
Background:
- Neutrophil (PMN) activation precedes tissue damage in ischemia-reflow states of coronary artery disease.
- Atrial natriuretic peptide (ANP) release from myocytes occurs rapidly after myocardial ischemia onset.
- A potential role for ANP in PMN activation warrants investigation.
Purpose of the Study:
- To investigate the effects of ANP on polymorphonuclear leukocyte (PMN) functions in vitro.
- To determine if ANP acts as a preinflammatory substance in ischemia-reperfusion.
Main Methods:
- In vitro testing of ANP effects on PMN functions.
- Utilizing triggering stimuli like phorbol 12-myristate 13-acetate, opsonized zymosan, and FMLP.
- Assessing ANP fragments' effects on respiration burst and beta-glucuronidase release.
Main Results:
- ANP primes PMN respiration burst, enhancing superoxide anion secretion.
- Specific ANP fragments (1-28 and 7-28) enhanced respiration burst activity.
- ANP stimulated beta-glucuronidase release and inhibited FMLP-stimulated PMN chemotaxis, possibly via enhanced adhesiveness.
Conclusions:
- Atrial natriuretic peptide (ANP) significantly regulates key PMN functional activities.
- ANP acts as a preinflammatory substance in ischemia-reperfusion states and myocardial necrosis.
- Structure-activity relationships suggest ANP interacts with specific PMN receptors.
