A COMPARISON OF THE RATES OF DEVELOPMENT OF FUNCTIONAL HEXANE NEUROPATHY IN WEANLING AND YOUNG-ADULT RATS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 5  (1) , 63-68
Abstract
Chronic inhalation exposure of adult rats to hexane caused neural toxicities to develop over several wk. Because the developing organism is in many cases more vulnerable to toxic insult than the adult, and children make up a substantial proportion of the population of solvent abusers, the effects of exposing weanling and young adult rats to 1000 ppm hexane for 24 h/day, 6 days/wk, for 11 wk were compared. Within 2 wk of exposure, significant decreases in body weight and grip strength were observed in rats of both ages. The subsequent effects of the treatment on these indices of toxicity were greater in the young adults than in the rats first exposed as weanlings. The older rats also exhibited earlier and more severe signs of hindlimb flaccid paralysis. The effects of hexane on tail nerve conduction time and on the brainstem auditory-evoked response were about the same in rats of both ages, with latencies increasing compared to controls over the exposure period. The relative resistance of the weanling rats to hexane neuropathy may have been due to shorter, smaller-diameter axons, or to a greater rate of growth and repair in their peripheral nerves compared to those of adults.