4119 Mesaconitine Mesaconitine is one of the Aconitum sp. alkaloids. It stimulates β-adrenoceptors and the consequent activation of intracellular processes can lead to the long-lasting changes in excitability. 2752-64-9 416228 C33H45NO11 White powder. Mesaconitine (MA) is one of the Aconitum sp. alkaloids. The primary toxicity of Aconitum sp. alkaloids is on the heart and the central nervous system. They can induce cardiac flutter or fibrillation, ventricular arrhythmias, and repetitive after-potentials and oscillations following nerve stimulation. The electrophysiological mechanism of the arrhythmogenic effect of aconitine is a delay in the final repolarization phase of the action potential, which initiates premature or triggered excitations. These are due to a removal of inactivation of voltage-dependent Na+ channels. Due to the massive influx of Na+, the excitation is followed by complete inexcitability of nerve cells. Aconitum sp. alkaloids evoke dopamine release from dopaminergic neurons; then excessive extracellular dopamine creates stresses on cellular antioxidant systems and induces neuron apoptosis. They are known cardiotoxins and neurotoxins, and also have embryotoxicity and cytotoxicity. (A15426) Mesaconitine activates inhibitory noradrenergic neurones of descending inhibitory pathways. Mesaconitine is capable of evoking a long-lasting excitatory action at a low concentration, a depressant action at high concentrations and biphasic effects in an intermediate concentration range, probably via the involvement of the noradrenergic system. The biphasic effect observed during application of 30 and 100 nM mesaconitine is similar to the action of noradrenaline in the rat hippocampal CA1 region. The fact that the two different kinds of actions evoked by 30 and 100 nM mesaconitine in a biphasic manner are selectively prevented by pretreatment with a- and b-adrenoceptor antagonists provides evidence that the effects involve activation of a- and b-receptors. (A15427) No indication of carcinogenicity to humans (not listed by IARC). 2014-08-29T05:01:08Z 2014-12-24T20:26:37Z C08698 true COCC12CN(C)C3C4C(OC)C1C3(C1CC3(O)C(OC(=O)C5=CC=CC=C5)C1C4(OC(C)=O)C(O)C3OC)C(CC2O)OC C33H45NO11 InChI=1/C33H45NO11/c1-16(35)45-33-21-18(13-31(39,28(43-6)26(33)37)27(21)44-29(38)17-10-8-7-9-11-17)32-20(41-4)12-19(36)30(15-40-3)14-34(2)25(32)22(33)23(42-5)24(30)32/h7-11,18-28,36-37,39H,12-15H2,1-6H3 InChIKey=XUHJBXVYNBQQBD-UHFFFAOYNA-N 631.7105 631.299261287 Exogenous Solid 390349