HISTOLOGICAL AND TEMPORAL CHARACTERISTICS OF NIGRAL TRANSNEURONAL DEGENERATION AFTER STRIATAL INJURY

Neurotoxic injury of the caudate-putamen and lateral globus pallidus u nilaterally initiated transneuronal degeneration of neurons in the ips ilateral substantia nigra reticulata (SNR). Quantification of SNR neur ons using unbiased stereology demonstrated that neuron loss began 4 da ys after the initial striatal lesion, followed by significant loss (50 %) at 6 days and a plateau at 8 days. Analysis at the light and ultras tructural levels revealed morphological changes consistent with a type of programmed cell death. These temporal and histological results ref ine an in vivo model in which to explore mechanisms of delayed neurona l degeneration. (C) 1998 Elsevier Science B.V. All rights reserved.