Desenvolupament de metodologia analítica per la determinació de neurotòxics i els seus metabòlits en sang de ratolí per cromatografia

Abstract

The IDPN is an ototoxic nitrile that kills the vestibular cells of experimental animals. These cells are related to motor skills like balance, visual stabilization and body acceleration as has been observed in mice that were administered with this substance. It is believed that the increase in neurodegenerative diseases and the loss of these skills with aging could be related with the increasingly presence of nitriles on the environment. Currently the metabolic pathway that follows the IDPN in the body is unknown, although several hypotheses have been described which result in three metabolites: BAPN, β-alanine and cyanoacetic acid as these compounds have been detected in urine of rats. In the development of animal models to study the relationship of nitriles with neurodegenerative diseases it is essential to develop analytical methodologies for detecting and quantifying these compounds on biological samples that will be able to establish a direct relationship between their presence in the experimental animal bodies, which causes motor diseases, and their effects on the vestibular system that leads to vestibular cells death. For this reason, the objective of the present study is to develop an analytical method by liquid chromatography for detecting and quantifying them in blood samples. In this study, we have determined the experimental conditions for each stage of the analytical method: detection and determination of IDPN and its possible metabolites, treatment of blood samples, derivatisation of the samples, chromatographic conditions, calibration and recoveries. The method has been applied to the analysis of mice’s blood samples after administration of 24mg / kg dose of IDPN for several days. We have also analyzed the relationship between the concentrations of its metabolites, 3-aminopropionitril (BAPN) and β-alanine, in plasma with behavioural and vestibular immunohistologic studies of the same group of mices. The results indicate an inverse relationship between the concentrations of metabolites in blood and the vestibular damage caused by IDPN