Thiamine cardiotropism.

Thiamine administration (200 mg/kg 2 hours before start of the experiment) substantially reduced the myocardial ischaemic lesion in a model of experimental myocardial infarction in the rat. As shown by stereometric analysis of histological heart preparations, the cytoprotective action of vitamin B1 is mediated by increased cardiomyocyte resistance towards ischaemia, i.e., through an adequate increase in the relative volume of the protection zone. Experiments on a model of emotional-painful stress in the rat show that the antiischaemic action of vitamin B1 cannot be explained by a specific cardiotropism of thiamine (the presence of thiamine phosphate buffer depots excludes the manifestation of coenzymatic effects of thiamine under given conditions) but by an antistressor action of thiamine resulting in exclusion of an important pathogenetic link in the mechanism of stress-conditioned cardiopathy.