Direct evidence of bradycardic effect of omega-3 fatty acids acting on nucleus ambiguus

Neurosci Lett. 2020 Sep 14:735:135196. doi: 10.1016/j.neulet.2020.135196. Epub 2020 Jun 22.

Abstract

Docosahexaenoic acid (DHA) an omega-3 polyunsaturated fatty acid, is an agonist of FFA1 receptor. DHA administration reduces the heart rate via unclear mechanisms. We examined the effect of DHA on neurons of nucleus ambiguus that provide the parasympathetic control of heart rate. DHA produced a dose-dependent increase in cytosolic Ca2+ concentration in cardiac-projecting nucleus ambiguus neurons; the effect was prevented by GW1100, a FFA1 receptor antagonist. DHA depolarized cultured nucleus ambiguus neurons via FFA1 activation. Bilateral microinjection of DHA into nucleus ambiguus produced bradycardia in conscious rats. Our results indicate that DHA decreases heart rate by activation of FFA1 receptor on cardiac-projecting nucleus ambiguus neurons.

Keywords: DHA; Docosahexaenoic acid; FFA1 receptor; Parasympathetic cardiac tone.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Bradycardia / chemically induced*
  • Bradycardia / physiopathology
  • Cells, Cultured
  • Fatty Acids, Omega-3 / administration & dosage*
  • Heart Rate / drug effects*
  • Heart Rate / physiology*
  • Male
  • Medulla Oblongata / drug effects*
  • Medulla Oblongata / physiology*
  • Microinjections
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Fatty Acids, Omega-3