FUNCTION OF THE AUDITORY AND VISUAL SYSTEMS, AND OF PERIPHERAL-NERVE,IN RATS AFTER LONG-TERM COMBINED EXPOSURE TO N-HEXANE AND METHYLATED BENZENE-DERIVATIVES .2. XYLENE
P. Nylen et M. Hagman, FUNCTION OF THE AUDITORY AND VISUAL SYSTEMS, AND OF PERIPHERAL-NERVE,IN RATS AFTER LONG-TERM COMBINED EXPOSURE TO N-HEXANE AND METHYLATED BENZENE-DERIVATIVES .2. XYLENE, Pharmacology & toxicology, 74(2), 1994, pp. 124-129
Rats were exposed to xylene, to n-hexane, or to xylene together with n
-hexane, each solvent 1000 p.p.m. (1000 + 1000 p.p.m. in mixed exposur
e), 18 hr/day, 7 days/week during 61 days. Neurophysiological recordin
gs were made 2 days, 4 months, and 10 months after the end of exposure
. Exposure to n-hexane alone, or xylene alone, caused a slight loss of
auditory sensitivity as recorded by auditory brainstem response 2 day
s after the exposure. Exposure to n-hexane together with xylene caused
persistent loss of auditory sensitivity (7-17 dB; P < 0.05) which was
non-additively enhanced (P < 0.01). The latencies of the flash evoked
potentials in the group exposed to n-hexane alone were prolonged (re
C group) 2 days after exposure, while smaller prolongations were found
in the group exposed to xylene together with n-hexane. Exposure to n-
hexane alone caused a marked decrease in nerve conduction velocity, wh
ile simultaneous exposure to xylene inhibited n-hexane-induced velocit
y reduction in peripheral nerve (P < 0.01).