Capillary electrophoretic measurement of tissue metabolites

Abstract

A method for the measurement of tissue metabolites from rabbit urinary bladder using capillary electrophoresis (CE) has been developed. The method generates a reproducible electropherogram containing >20 peaks, including NAD, NADH, lactate, UDP-glucose, phosphocreatine, creatine, ATP, ADP, GTP, and UTP, from <20 nl of extract solution generated from 1.1 nl (or ∼1.2 μg) of tissue in <40 min. Multiple samples from the same bladder produce SE comparable with enzymatic or nuclear magnetic resonance (NMR) measurements of metabolites: phosphorus-NMR measurement requires 106 more tissue than CE; individual enzymatic measurements using 100 μl/sample require 2,000 μl, a 105 greater volume than required by CE for the same number of metabolites. CE detects about three times more peaks than phosphorus-NMR on a similar time scale. Comparable measurements using enzymatic analysis would require ∼10 times longer. The combination of minimal tissue volume requirements, rapid measurement, and reproducibility makes CE a valuable tool in the investigation of simultaneous changes in multiple metabolites from minute tissue samples.