Neuropathology of tuberous sclerosis

In the cerebrum of patients with tuberous sclerosis (TSC), there are three types of nodular lesions: cortical tubers, subcortical heterotopic nodules and subependymal giant cell astrocytomas. Histologically, these hamartias a nd hamartomas contain abnormal giant cells that show evidence of abnormal d ifferentiation of immature neural cells. Recent identification of the TSC1 and TSC2 genes has facilitated studies of the molecular pathology of TSC. T he expression of their protein products, hamartin and tuberin, is altered i n various TSC lesions. However, the molecular mechanism by which cortical t ubers develop remains to be elucidated. The Eker rat, a naturally occurring animal model of TSC, will provide a powerful tool for future investigation s of TSC. (C) 2001 Elsevier Science B.V. All rights reserved.