[Antivitamin activity of thiaminase from freshwater bicuspid molluscs after parenteral administration of the enzyme to albino mice].

Thiaminase from bicuspid mollusc, after a single administration into mice (25 or 50 un, subcutaneously), caused a decrease in the activity of transketolase and alpha-ketoglutaric acid dehydrogenase in the animal tissues within 3 hrs. The maximal antivitaminous effect of thiaminase was manifested within 2-5 days and slightly decreased within 7 days (at a dose of 25 un). Amount of thiamin was decreased in mice liver tissue from 6.54+/-0.36 mcg/g to 4.84+/-0.23 mcg/g within the second day after the thiaminase administration. Transketolase and alpha-ketoglutarate dehydrogenase from liver and kidney were more sensitive to the antivitaminous effect of thiaminase. General condition of the animals was not altered by parenteral administration of thiaminase during a week. Thiaminase may be recommended for modelling of thiamin deficiency in animals maintained at conventional diets.