Effects of CaSR on vascular relaxation/constriction in rats / 局解手术学杂志

ABSTRACT

Objective To investigate the effects of calcium sensing receptor (CaSR)on vasorelaxation/vasoconstriction of superior mes-enteric artery (SMA)in rats and its relationship to endothelium.Methods With endothelium-intact and endothelium-denuded SMA rings of rats,the effects of CaSR-specific allosteric modulator cinacalcet on the SMA rings pre-contracted with norepinephrine (NE),and vascular contractile response /relaxation reactivity were observed.Results Cinacalcet had no effects on resting tension of SMA rings with or without endothelium.Cinacalcet caused a significant relaxation in the endothelium-intact SMA rings pre-contraction with NE in a dose-dependent manner.Endothelium denudation abolished cinacalcet-induced vasorelaxation.Pretreatment with cinacalcet for 30 minutes decreased the con-tractile response of endothelium-intact SMA rings to NE,but had no significant influence on relaxation reactivity.In the endothelium-denuded SMA rings,cinacalcet did not affect both vasoconstriction and vasorelaxation.Conclusion CaSR plays an important role in the regulation of the vascular reactivity,and this effect is endothelium-dependent.