Modulation of acute transient exercise-induced hypertension after oral administration of four angiotensin-converting enzyme inhibitors in normotensive horses

• Published in: The veterinary journal (1997) 2016-02, Vol.208, p.33-37
• Main Authors: Muñoz, Ana, Esgueva, María, Gómez-Díez, Manuel, Serrano-Caballero, Juan Manuel, Castejón-Riber, Cristina, Serrano-Rodríguez, Juan Manuel
• Format: Article
• Language: English
• Subjects: Acetylcholinesterase - blood; Administration, Oral; Angiotensin-converting enzyme inhibitors; Angiotensin-Converting Enzyme Inhibitors - administration & dosage; Angiotensin-Converting Enzyme Inhibitors - pharmacology; Animals; Antihypertensive Agents - administration & dosage; Antihypertensive Agents - pharmacology; Blood pressure; Blood Pressure - drug effects; Equine; Exercise; Female; Horse Diseases - drug therapy; Horse Diseases - etiology; Horses; Hypertension; Hypertension - drug therapy; Hypertension - etiology; Hypertension - virology; Male; Physical Conditioning, Animal
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2015.10.036

•Angiotensin-converting enzyme inhibitors (ACEI) were administered before exercise to normotensive horses.•The effects of ACEIs in response to physiological hypertension were investigated.•Enalapril and quinapril induced similar reductions in exercise-induced hypertension.•Ramipril reduced physiological hypertension more than enalapril and quinapril.•Benazepril at 0.50 mg/kg maintained normotension after maximal exercise. Changes in blood pressure (BP) during acute hypertension in response to angiotensin-converting enzyme inhibitors (ACEIs) have not been investigated in normotensive horses. In this study, six healthy horses were subjected to five trials, consisting in a treadmill exercise workload of 8 m/s for 1 min, 2 h after oral administration (PO) of placebo (0 mg/kg), enalapril (2.0 mg/kg), quinapril (1.0 mg/kg), ramipril (0.2 mg/kg) or benazepril (0.5 mg/kg). Serum angiotensin converting enzyme (ACE) activity was measured and systolic (SBP) and diastolic (DBP) blood pressures were recorded at rest (R), 2 h after placebo or ACEI administration (pre-E) and within the first 20 s after exercise (post-E). Mean maximum serum ACE inhibition 2 h after PO administration was 4.8% (placebo), 39.4% (enalapril), 46.4% (quinapril), 55.0% (ramipril) and 71.68% (benazepril). There were no significant differences in serum ACE inhibition between enalapril and quinapril. SBP and DBP at times R and pre-E were not different in any of the five trials. In response to exercise, SBP increased by 67.6% (placebo), 52.7% (enalapril), 43.1% (quinapril), 26.6% (ramipril) and 4.2% (benazepril). In response to exercise, DBP increased by 20.6, 13.2, 11.7, 16.6 and 3.7% after placebo, enalapril, quinapril, ramipril and benazepril administration, respectively. Serum ACE activity changed during exercise, but statistical significance was not achieved. In conclusion, administration of PO benazepril at a dose of 0.5 mg/kg modulated physiological hypertension induced by exercise in horses that were otherwise normotensive.