The role of l-type calcium channels in the mediation of fast oscillation of arterial blood pressure and renal blood flow in rats

Abstract

The investigation of dynamic characteristics of blood pressure and renal blood flow provides detailed information about the fast regulatory mechanisms involved in arterial blood pressure (ABP) and renal blood flow (RBF) autoregulation. The aim of our study was to investigate the role of L-type Ca2+ channels in the mediation of fast oscillations of arterial blood pressure and renal blood flow in rats by means of spectral analysis. The experiments were performed on anesthetized male Wistar rats (n=7) at the age of 12-14 weeks. The ABP was measured directly in femoral artery; RBF was registered by perivascular ultrasonic Doppler probe (Transonic system) in control and experimental period. The spectrograms from APB and RBF were derived in Lab View 3.11 software. In experimental period the selective L-type Ca2+ channel blocker amlodipine besylate (AML) in dose 200 mkg.kg-1 bolus followed by 50 mkg.kg-1.h infusions was applied. Our results by using a spectral method of analysis of ABP and RBF confirmed involvement of L-type Ca2+ channels in the mediation of dynamic nature of myogenic vascular response. The L-type Ca2+ channels in different specific manner participate in the regulation of renal blood flow and arterial blood pressure.