Abstract

Objective-To study long-term effects of enalapril, an angiotensin-converting enzyme inhibitor, and hydralazine, an arteriodilator, on renin-angiotensin-aldosterone system and fluid balance before and after administration of furosemide.Animals-22 dogs with clinical signs of congestive heart failure (CHF) attributable to mitral regurgitation.Procedure-After initial examination, 12 dogs received enalapril and 10 received hydralazine. Dogs were re-examined 3 weeks and 6 months after initial examination. Furosemide was added after the 3-week examination, and at 6 months, dogs had received furosemide for at least 4 months.Results-Angiotensin II and aldosterone plasma concentrations were low before treatment, and only aldosterone became significantly decreased after enalapril monotherapy. Concentrations of both hormones and heart rate increased in dogs receiving hydralazine monotherapy, and fluid retention was evident. After long-term treatment with either of the 2 drugs together with furosemide, angiotensin II and aldosterone values increased in both groups. Natriuresis and kaliuresis developed in ail dogs, with greatest effect in those receiving enalapril and furosemide. These dogs had decreased plasma sodium concentration, whereas potassium concentration was equally decreased in both groups. After 6 months, the enalapril group, but not the hydralazine group, had increased cardiac size. All dogs had moderate reduction of weight and were azotemic, although changes were more pronounced in those of the hydralazine group.Conclusion-The 2 drugs have different effects on the renin-angiotensin-aldosterone system and fluid balance in dogs with CHF.

Published in

American Journal of Veterinary Research
1996, Volume: 57, number: 11, pages: 1645-1652
Publisher: AMER VETERINARY MEDICAL ASSOC

SLU Authors

• Häggström, Jens

  • Department of Physiology, Swedish University of Agricultural Sciences
    

• Hansson, Kerstin

  • Department of Animal Physiology, Swedish University of Agricultural Sciences
    
  • Department of Clinical Radiology, Swedish University of Agricultural Sciences
    

• Kvart, Clarence

  • Department of Physiology, Swedish University of Agricultural Sciences
    

• Madej, Andrzej

  • Department of Physiology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Clinical Science


Publication identifier

DOI: https://doi.org/10.2460/ajvr.1996.57.11.1645

Permanent link to this page (URI)

https://res.slu.se/id/publ/83990