Adenosine deaminase and adenosine attenuate ventricular arrhythmias caused by norepinephrine

G. S. Friedrichs, G. F. Merrill

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


Twenty-five beagles weighing 9.1 ± 0.4 kg were used to investigate the arrhythmogenic effects of divided doses of intracoronary norepinephrine (50-200 ng·kg-1·min-1) in the absence and the presence of adenosine deaminase (5 U·kg-1·min-1). A dose of norepinephrine (100 ng·kg-1·min-1) that caused 66 ± 17% ectopy in the absence of adenosine deaminase caused only 16 ± 14% ectopy (P < 0.05) in the presence of the enzyme. Ventricular tachycardia caused by 200 ng·kg-1·min-1 norepinephrine was reduced from 1.2 ± 0.3 to 0.1 ± 0.1 bouts/10 cardiac cycles (P < 0.05) by adenosine deaminase. In five additional dogs, intracoronary adenosine (0.11 μmol/min) terminated sustained norepinephrine-induced (200 ng·kg-1·min-1) ventricular tachycardia within 23 ± 9 s (P < 0.05). As long as the adenosine infusion was maintained, a normal sinus rhythm was observed. We conclude that both adenosine and adenosine deaminase significantly attenuate norepinephrine-induced ventricular arrhythmias. A common element beyond the deamination of adenosine, quite possibly ammonia, appears to account for these results.

Original languageEnglish (US)
Pages (from-to)H979-H984
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Issue number3 29-3
StatePublished - 1991

All Science Journal Classification (ASJC) codes

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)


  • Catecholamine
  • Ectopy
  • Ventricular tachycardia

Fingerprint Dive into the research topics of 'Adenosine deaminase and adenosine attenuate ventricular arrhythmias caused by norepinephrine'. Together they form a unique fingerprint.

Cite this