Effects of methyl butyl ketone on peripheral nerves and its mechanism of action.
DeJesus-CP; Pleasure-DF; Asbury-AK; Brown-MJ; Paradise-CM
Department of Neurology, Yale University, :1-27
The effects of methyl-n-butyl-ketone (591786) (MBK) and methylethyl- ketone (78933) (MEK) on the peripheral nerves of rats were investigated. Rats were exposed 6 hours a day, 5 days a week to: 60 parts per million (ppm) of MBK or 2150 ppm of MEK for 6 weeks; MBK, 100 ppm and MEK 4740 ppm for 4 weeks; or MBK, 1050 ppm and 1450 ppm for 5 weeks. The animals were weighed and examined periodically for electrophysiological and biochemical abnormalities. MBK produced peripheral neuropathy as evidenced by abnormalities of the sciatic and tibial nerves and giant axonal swellings in rats while MEK did not. Decreased weight gain, electrophysical and morphological deterioration were evident before signs of neuropathy developed at the 9th to 10th week of exposure. The motor nerve conduction velocity decreased progressively until the end of the exposure time after which it gradually normalized. The decrease in the evoked muscle action potential amplitude occurred later and did not normalize with full clinical recovery. The biochemical studies did not show evidence of demyelination, Wallerian degeneration or fibrosis.
Ketones; Peripheral-nervous-system; Laboratory-animals; Pathogenicities; Nervous-system-disorders; Analytical-methods; Muscle-functions
Final Contract Report
Final Report Contract No. Penn CDC 99-76-16, U.S. Department of HEW, CDC, PHS, NIOSH, Cincinnati, Ohio, 27 pages, 45 references
Department of Neurology Yale University New Haven, CT