Brain metallothionein in stress.

Brain metallothionein (MT) levels have been measured in the rat brain in basal and stress situations with polyclonal antibodies which do not cross-react significantly with the brain-specific MT isoform growth inhibitory factor (MT-III). Acute immobilization stress increases MT levels in most but not all brain areas. In contrast, chronic immobilization stress has no effect on MT levels. Although glucocorticoids and monoamines appear to have a role in brain MT regulation in control rats, they do not appear to have a vital role in stressed rats. Experiments with primary cultures enriched in neurons or astrocytes indicate that MT is present in both cell types and that responds to the well-known MT inducers zinc, copper and glucocorticoids.