Brain, Neuron - Cell Loss

Neuronal cell loss in a female F344/N from a 2-year study. Note the loss of neurons in CA3 region of the hippocampus (arrows).
Figure 1 of 3

Normal number and morphology of CA3 neurons (arrow) in a control male rat from a single-dose acute gavage study.
Figure 2 of 3
comment:
Knowledge of the normal neuroanatomic structure of specialized regions of the brain (hippocampus, cerebellum) is necessary to detect neuronal cell loss. It is generally accepted that routine subjective light microscopy detects only significant reductions in cell numbers. Quantitation of more subtle losses requires special staining with glial fibrillary acidic protein or cresyl violet or with more sophisticated techniques of morphometry and stereology. Figure 1


recommendation:
In NTP studies, any detected reduction in neuronal populations should be subjectively graded in severity and diagnosed as Neuron, Cell loss. Affected subsites of the brain should be noted and included in the narrative. In the presence of concurrent lesions, lesions with the most severity are typically diagnosed. Other concurrent lesions may be diagnosed separately, if warranted by the severity.references:
Ozaki HS, Murakami TH, Shimada M. 1983. Learning deficits on avoidance task and hippocampal lesions in area CA3 following intraperitoneal administration of 3-acetylpyridine. J Neurosci Res 10(4):425-435. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/6686615
Purpura DP, Gonzalez-Monteagudo O. 1960. Acute effects of methoxypyridoxine on hippocampal end-blade neurons; an experimental study of “special pathoclisis” in the cerebral cortex. J Neuropathol Exp Neurol 19:421-432. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/14435353
Web page last updated on: June 13, 2014