Abstract
Thiamine (T) analogues pyrithiamine, oxythiamine or amprolium in amounts 10–1000 times higher than labelled T, were i.p. injected into rats together with 14C-T (30 μg; 46.25 KBq). The radioactivity associated with T and its phosphoesters in the plasma and cerebral cortex, brainstem, cerebellum, and sciatic nerve were determined at time intervals from 0.25 to 240 h from injection. The experimental data obtained were processed with a mathematical compartmental model that calculated the fractional rate constants. These are the amount of content in a given compartment that is replaced in 1 h and expressed in per hour. The results showed that all three analogues inhibited thiamine entry from plasma. Instead, oxythiamine enhanced T phosphorylation to T pyrophosphate (TPP); amprolium and oxythiamine enhanced TPP dephosphorylation to monophosphate (TMP); pyrithiamine reduced TPP dephosphorylation and TMP formation, while none of the analogues modified TMP dephosphorylation to T. In conclusion, in living rats, the action of T analogues was much more complex than could be expected from their structure and action in vitro.
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Bellazzi, R., Magni, P., and Denicolao, G. (1997). Dynamic probabilistic networks for modelling and identifying dynamic systems: A MCMC approach. Intell. Data Anal. Int. J. 1(4):245-262.
Cooper, J.R., and Kini, M.M. (1972). The partial purification and characterization of thiamine pyrophosphatase from rabbit brain. J. Neurochem. 19:1809-1811.
Glantz, S.A. (1988). Statistica per Discipline Biomediche. Programma Applicativo, MacGraw-Hill, Milano, Italy.
Magni, P., Bellazzi, R., and Denicolao, G. (1998). Bayesian function learning using MCMC methods. IEEE Trans. Pattern Anal. Mach. Intell. 20(12):1319-1331.
Magni, P., Bellazzi, R., Nauti, A., Patrini, C., and Rindi, G. (2001). Compartmental model identification based on an empirical Bayesian approach: The case of thiamine kinetics in rats. Med. Biol. Eng. Comput. 39:700-706.
Morita, M., Kanaya, T., and Minesita, T. (1968). Uptake of pyrithiamine by tissues of rats in relation to tissue thiamine levels. J. Vitaminol. 14:77-82.
Nauti, A., Patrini, C., Reggiani, C., Merighi, A., Bellazzi, R., and Rindi, G. (1997). In vivo study of the kinetics of thiamine and its phosphoesters in the deafferented rat cerebellum. Metab. Brain Dis. 12:145-160.
Patrini, C., Nauti, A., and Rindi, G. (1998). Thiamine pyrophosphate-dependant and thiamine metabolizing enzymes in the deafferented cerebellum and in the intact cerebral cortex of rat. Metabol. Brain Dis. 13:21-27.
Patrini, C., Perucca, E., Reggiani, C., and Rindi, G., (1993). Effects of phenytoin on the in vivo kinetics of thiamine and its phosphoesters in rat nervous tissues. Brain Res. 628:179-186.
Patrini, C., Reggiani, C., Laforenza, U., and Rindi, G. (1988). Blood-brain transport of thiamine monophosphate in the rat: A kinetic study in vivo. J. Neurochem. 50:90-93.
Patrini, C., and Rindi, G. (1980). An improved method for the electrophoretic separation and fluorometric determination of thiamine and its phosphates in animal tissues. Int. J. Vit. Nutr. Res. 50:10-18.
Randoin, L., and Causeret, J. (1947). Constitution d'un régime alimentaire équilibré pour les jeunes rats blancs destinés au dosage des vitamines A et D par les méthodes biologiques. Bull. Soc. Hyg. Aliment. 35:14-18.
Reggiani, C., Patrini, C., and Rindi, G. (1984). Nervous tissue thiamine metabolism in vivo. I. Transport of thiamine and thiamine monophosphate from plasma to different brain regions of the rat. Brain Res. 293:319-327.
Rindi, G., Comincioli, V., Reggiani, C., and Patrini, C. (1984). Nervous tissue thiamine metabolism in vivo. II. Thiamine and its phosphoesters dynamics in different brain regions and sciatic nerve of the rat. Brain Res. 293:329-342.
Rindi, G., Comincioli, V., Reggiani, C., and Patrini, C. (1987). Nervous tissue thiamine metabolism in vivo. III. Influence of ethanol intake on the dynamics of thiamine and its phosphoesters in different brain regions and sciatic nerve of the rat. Brain Res. 413:23-35.
Rindi, G., de Giuseppe, L., and Ventura, U. (1963). Distribution and phosphorylation of oxythiamine in rat tissues. J. Nutr. 81:147-154.
Rindi, G., Ferrari, G., Ventura, U., and Trotta, A. (1966). Action of amprolium on the thiamine content of rat tissues. J. Nutr. 89:197-202.
Rindi, G., Patrini, C., Comincioli, V., and Reggiani, C. (1980). Thiamine content and turnover rates of some rat nervous regions, using labeled thiamine as a tracer. Brain Res. 181:369-380.
Rindi, G., and Perri, V. (1961). Uptake of pyrithiamine by tissues of rats. Biochem. J. 80:214-216.
Rogers, E.F. (1962). Thiamine antagonists. Ann. N.Y. Acad. Sci. 98:412-429.
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Rindi, G., Patrini, C., Nauti, A. et al. Three Thiamine Analogues Differently Alter Thiamine Transport and Metabolism in Nervous Tissue: An In Vivo Kinetic Study Using Rats. Metab Brain Dis 18, 245–263 (2003). https://doi.org/10.1023/B:MEBR.0000020187.98238.58
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DOI: https://doi.org/10.1023/B:MEBR.0000020187.98238.58