Static Magnetic Field and Calcium Channel Blocking agent Combined Effect on Baroreflex Sensitivity in Rabbits

Abstract

The objective was to study the static magnetic field (SMF) effect on sinocarotid baroreceptors with decreased baroreflex sensitivity (BRS) induced by verapamil administration. BRS was studied in rabbits. Fifty-four experimental runs (27 sham controls, and 27 SMF series) were made with a steady-state method that measured changes in heart rate (HR) during phenylephrine-induced increases in arterial blood pressure, and by means of spectral analysis of blood pressure and HR variations, estimating the transfer function from mean arterial blood pressure to HR. Rabbits were under sedation induced by pentobarbital infusion (5 pg/kg/h). BRS was measured before and after 40 min of sham or 0.35 T Nd₂,-Fe₁₄,-B alloy magnet local exposure to the sinocarotid baroreceptor region, accompanied by the calcium channel blocking agent (verapamil infusion at 20μg/kg/min). We found that SMF prevented the significant decrease of BRS induced by verapamil administration. Results obtained may have clinical impact with respect to the association of BRS decrease with severe cardiovascular pathology.