Vasorelaxant effect of fluoxetine in isolated rat aorta

흰쥐 대동맥에서 fluoxetine의 혈관 이완 효과

  • Kim, Shang-Jin (Bio-Safety Research Institute, Chonbuk National University) ;
  • Kang, Hyung-sub (Bio-Safety Research Institute, Chonbuk National University) ;
  • Kim, Jin-shang (Bio-Safety Research Institute, Chonbuk National University)
  • 김상진 (전북대학교 생체안전성연구소) ;
  • 강형섭 (전북대학교 생체안전성연구소) ;
  • 김진상 (전북대학교 생체안전성연구소)
  • Accepted : 2004.08.25
  • Published : 2004.12.30


The vasorelaxant effect of serotonin reuptake inhibitor fluoxetine was investigated in rat isolated thoracic aorta. Fluoxetine induced a concentration-dependent relaxation in aorta precontracted with phenylephrine (PE) and KCl. These relaxations were suppressed by removal of the endothelium (-E) or pretreatment of nitric oxide synthase inhibitors, N(G)-nitro-L-arginine (L-NNA) and N(omega)-nitro-Larginine methyl ester (L-NAME), guanylate cyclase inhibitors, methylene blue (MB) and 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ), and $Ca^{2+}$ channel blockers, nifedipine and verapamil, in PE-precontracted +E rings. However, fluoxetine-induced relaxations were not suppressed by pretreatment of $K^{+}$ channel blockers, tetrabutylammonium and glibenclamide, in PE-precontracted endothelium intact (+E) rings. The fluoxetine-induced relaxations were not suppressed by removal of the endothelium or pretreatment of LNNA and MB in KCl-precontracted +E rings. Also, fluoxetine inhibited PE-induced sustained contraction in +E rings. These inhibitory effects of fluoxetine on contractions could be reversed by removal of the endothelium or pretreatment of L-NNA, L-NAME, MB, ODQ, nifedipine and verapamil, but not by pretreatment of etrabutylammonium and glibenclamide. These findings suggest that the vasorelaxant effect of fluoxetine is modulated by intracellular $Ca^{2+}$ with an involvement of endothelial NO-cGMP pathway and also may be related to the inhibition of $Ca^{2+}$ entry through voltage-gated channel.


Supported by : 전북대학교


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