To investigate the possibility that thiamine has more than one vital role in the mammalian system, it was decided to use the antagonists pyrithiamine and oxythiamine, and to utilize carbon-14 labeled compounds to more effectively study the vitamin and the above-named antagonists. To make it more effective, we felt that perhaps differences between the localization of oxythiamine and pyrithiamine could be detected in the brain. We also considered and tested the possibility that either or both of the antagonists would alter the localization of thiamine. Essentially, two procedures were used in this study. One was a counting method and the other an autoradiographic study. The counting method was used to determine whether or not the brain was permeable to oxythiamine, as it is to pyrithiamine, and if so, to what extent. The autoradiographic method was utilized to check the counting method as to the brain's permeability to oxythiamine, and to determine thiamine and oxythiamine localization, if any. Both methods indicated the penetration of oxythiamine into brain tissues, but further work must be done to determine whether or not the amount is physiologically important. The results of the autoradiographic technique indicated the localization of thiamine in the gray matter of the brain to a greater extent than in the white matter. This would indicate that the thiamine is more important around the cell nuclei than it is in the fibers. The autoradiographs indicated also that oxythiamine penetrated the brain in lesser amounts than did thiamine, but localized in essentially the same areas. These results suggest the need for a great deal more work before the functions of thiamine and the effects of the antagonists, oxythiamine and pyrithiamine can be fully clarified.



College and Department

Chemistry and Biochemistry



Date Submitted


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Vitamin B1