Before the official start of the study, to determine the appropriate dosing interval and a preliminary assessment of drug safety, first carried out the pre-trial, 4 subjects with different gender in half, after 7 days of run-in period, collect baseline background sampling point at day 4, no medication but water intake. At day 8 fasting oral propionyl L-carnitine hydrochloride tablets 0.5g, according to pre-designed schedule for blood samples, urine samples and clinical indicators, provide a reference for official trial.