Validated liquid chromatography-mass spectrometry method for the quantification of glycogenolysis phosphorylase inhibitor in mouse tissues - 5-isopropyl-4-(2-chlorophenyl)-1-ethyl-1,4-dihydro-6-methyl-2,3,5-pyridinetricarboxylic acid ester disodium salt hydrate.

5-Isopropyl-4-(2-chlorophenyl)-1-ethyl-1,4-dihydro-6-methyl-2,3,5-pyridinetricarboxylic acid ester disodium salt hydrate, is a noncompetitive inhibitor of glycogen phosphorylase - a critical enzyme in the process of glycogenolysis. This chemical compound is most widely used in studies focused on the inhibition of liver and muscle glycogenolysis. However, there are also reports linking phosphorylase inhibitor action with cognitive function and glycogen metabolism in the brain. The aim of this study was to develop and validate the liquid chromatography-mass spectrometry method for quantitative analysis of present chemical compound in mouse tissues including different brain regions. Obtained linearity was in the range of 10-550 ng/mL with a correlation coefficient of 0.9996. In tissue matrix samples the limit of detection was 7.76 ng/mL, while the limit of quantification was 23.29 ng/mL. The coefficient of variation values did not exceed ±15% for either within a run or between run precision quality control samples. The extraction recovery was between 89.44% and 98.70% for various validation analyte concentrations. The present method was successful in the quantitative determination of the presented analyte in mouse tissues and provided evidence that the compound is not only present in the liver, heart, and skeletal muscle but also in different regions of brain tissue such as the hippocampus, cerebellum, and cortex.