Distribution and activity of transglutaminase in rat brain carcinogenesis and in gliomas

Tissue transglutaminase is a calcium-dependent enzyme which may influence cell morphology, cytoskeletal processes and membrane functions. During rat brain carcinogenesis induced by transplacental administration of N-ethyl-N-nitrosourea to BD IX rats, cytosolic tissue transglutaminase activity was increased by about 140% at 30 days of extrauterine life and returned towards the control values at 3–5 months. In the particulate fraction, enzyme activity progressively increased, reaching values similar to those present in the developed gliomas. Tissue transglutaminase activity in gliomas had a behavior inverse to that observed in controls, with a decrease (about 50%) in the cytosol and a marked increase (380%) in the particulate fraction, indicating a redistribution of enzyme activity.