ABSTRACT
Objective A method of determination of methamphetamine, ketamine and morphine in saliva was established by super high performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). Methods The saliva samples after precipitation protein, in the ACQUITY UPLC BEH Phenyl(100mm×2.1mm,1.7μm) column chromatography, after the acetonitrile: 0.3% Formic acid solution gradient elution and through the ESI+ ionization mode MRM analysis and inspection. Results The linearity was estadlished in saliva between 4μg/L and 200μg/L, LOD was 0.2μg/L, LOQ was 4μg/L. the recovery was in the range of 87%-128%. Conclusion The method is simple, rapid and accurate for determination of methamphetamine, ketamine and morphine in saliva.
ABSTRACT
OBJECTIVE To explore the mechanism of methylamphetamine (MA) on heart toxicity. METHODS The effects of MA on delayed rectifier potassium current (IK) and action potential (AP) were analyzed in isolated decreased AP from 121.6 to 106.0 mV and delayed the action potential duration (APD), but had no effect on the resting potential. The 10%, 25%, 50%, 75% and 90% of APD (APD10, APD25, APD50, APD75 and APD90)inhibited the membrane potential of rapidly activating delayed rectifier potassium current (IKr) and slowly activating delayed rectifier potassium current (IKs), downward shifted the Ⅰ -Ⅴ curve, but had no effect on the curve shape and could be partly recovered after flushing. The tail current IKr was blocked concentration-dependently after simiarly inhibited by MA. CONCLUSION MA has inhibitory effects on Ik and AP in ventricular myocytes,which may be one of the possible electrophysiological mechanisms of the cardiac damage caused by MA.