Neuronal loss in hippocampus in rats exposed to toluene

  • 1 June 1996
    • journal article
    • research article
    • Vol. 17  (2) , 359-366
Abstract
Both clinical and epidemiological studies of the effects of exposure to toluene have shown that long-term exposure may result in chronic toxic encephalopathy, where one of the major symptoms is memory deficits. We have attempted to identify the structural basis of the toxic effects of toluene in the hippocampus, a region of the brain known to be involved in learning and memory processes and well suited for stereological analysis. Rats were exposed to 1 500 ppm of toluene, six hours per day, five days per week for six months. This was followed by a tb ur-mon th-period without exposure prior to sacrifice. The total number of neurons in each of the five subdivisions of hippocampus of six exposed and six control rats was estimated with the optical fractionator. A statistically significant neuron loss of 16% was found in regio inferior (CA3 and CA2) of the exposed rats. (C) 1996 Intox Press, Inc.