Cardio-ankle vascular index (CAVI) differentiates pharmacological properties of vasodilators nicardipine and nitroglycerin in anesthetized rabbits

J Pharmacol Sci. 2015 Aug;128(4):185-92. doi: 10.1016/j.jphs.2015.07.002. Epub 2015 Jul 14.

Abstract

Cardio-ankle vascular index (CAVI) has been developed for measurement of vascular stiffness from the aorta to tibial artery, which is clinically utilized for assessing the progress of arteriosclerosis. In this study, we established measuring system of the CAVI in rabbits, and assessed whether the index could reflect different pharmacological actions of nitroglycerin and nicardipine on the systemic vasculature. Rabbits were anesthetized with halothane, and the CAVI was calculated from the well-established basic equations with variables obtained from brachial and tibial blood pressure and phonocardiogram. Nicardipine (1, 3 and 10 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and heart-ankle pulse wave velocity (haPWV). Meanwhile, no significant change was detected in the CAVI at the low or middle dose, which reflects the defining feature of the CAVI that is independent of blood pressure. The index increased at the high dose. Nitroglycerin (2, 4 and 8 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and haPWV. Meanwhile, the CAVI was decreased during the nitroglycerin infusion, which may reflect its well-known pharmacological action dilating conduit arteries. These results suggest that the CAVI differentiates the properties of these vasodilators in vivo.

Keywords: Cardio-ankle vascular index (CAVI); Doxazosin; Nicardipine; Nitroglycerin; Phenylephrine.

MeSH terms

  • Anesthesia
  • Animals
  • Ankle Brachial Index / methods*
  • Arteriosclerosis / diagnosis
  • Blood Pressure / drug effects
  • Brachial Artery
  • Dose-Response Relationship, Drug
  • Female
  • Femoral Artery
  • Halothane
  • Male
  • Nicardipine / pharmacology*
  • Nitroglycerin / pharmacology*
  • Pulse Wave Analysis / methods*
  • Rabbits
  • Tibial Arteries
  • Vascular Resistance / drug effects
  • Vascular Stiffness / drug effects*
  • Vasodilator Agents / pharmacology*

Substances

  • Vasodilator Agents
  • Nicardipine
  • Nitroglycerin
  • Halothane