[Morphogenesis of thymus involution during oxythiamine B1-hypovitaminosis]

Atrophy of the thymus cortex was found in rats after administration of oxythiamine. In acute experiments, atrophy was a consequence of a short-term inhibition of proliferation followed by enhancement of disintegration of small thymocytes by caryorhexis. Disintegration assumes an exceptional significance for thymus involution. Breakdown of cells correlated with a sharp decrease in thymocyte resistance to hydrocortisone. Possible metabolic reasons for the decreased resistance are discussed.