P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stabl...P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stable analogue of ATP,can induce both pressor and depressor responses in la boratory animals.In this study,the effects of increasing intravenous doses of α,β-MeATP and noradrenaline(NA)(0-30 nmol/kg)administered at 20 min intervals on systolic(SBP),diastolic(DBP)and mean(MBP)blood pressure in groups of anesthetized mice(n=6)were compared.Both α,β-MeATP and NA caused transient,dose-dependent increases in SBP,DBP and MBP but the effect of α,β-MeATP was more rapid and significantly larger at doses of 10 and 30 nmol/kg(P<0.01).At the dose of 30 nmol/kg,α,β-MeATP increased SBP,DBP and MBP by 65.8±7.0,65.7±5.0 and 65.7±5.5 mmHg,respectively,compared to increases of 36.8±4.6,33.3±4.9 and 34.5±4.7 mmHg,respectively,produced by NA.These results indicate P2X_(1) receptors play an important role in BP regulation although purinergic vasoconstriction alone may not explain the more potent pressor response to α,β-MeATP in the anesthetized mouse.展开更多
文摘P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stable analogue of ATP,can induce both pressor and depressor responses in la boratory animals.In this study,the effects of increasing intravenous doses of α,β-MeATP and noradrenaline(NA)(0-30 nmol/kg)administered at 20 min intervals on systolic(SBP),diastolic(DBP)and mean(MBP)blood pressure in groups of anesthetized mice(n=6)were compared.Both α,β-MeATP and NA caused transient,dose-dependent increases in SBP,DBP and MBP but the effect of α,β-MeATP was more rapid and significantly larger at doses of 10 and 30 nmol/kg(P<0.01).At the dose of 30 nmol/kg,α,β-MeATP increased SBP,DBP and MBP by 65.8±7.0,65.7±5.0 and 65.7±5.5 mmHg,respectively,compared to increases of 36.8±4.6,33.3±4.9 and 34.5±4.7 mmHg,respectively,produced by NA.These results indicate P2X_(1) receptors play an important role in BP regulation although purinergic vasoconstriction alone may not explain the more potent pressor response to α,β-MeATP in the anesthetized mouse.
