Abstract
The aim of this study was to clarify neurological cause of the human disorder such as multiple chemical sensitivity and sick building syndrome, which is related to chronic exposure to low dose of volatile organic compounds (VOC). We chose toluene (Tol) and formaldehyde (FA) as VOC, and evaluated hippocampal CA1 synaptic transmission as a parameter of neurological memory function. In the case of Tol exposure, male C3H/He mice (8-wk old, n=5) were restrained to keep nose inserted into a chamber filled with 90 ppm Tol for 30-min, 7 times within 4-wk. In the case of FA exposure, female C3H/He mice (8-wk old, n=10) were exposed to 400ppb FA in a FA conc.-controllable chamber for 16-h a day, 5-d a week, for 12-wk. Within a few days from the last inhalation, each mouse was decapitated and hippocampal slices were prepared from the middle third of the hippocampus. By stimulation of Schaffer collaterals, field potential was recorded from stratum radiatum. Two parameters, I/O relationship of fEPSP and LTP induced by theta burst tetanic stimulation, were compared between exposed and control groups, and no significant difference was observed. Our results suggest that residential exposure to VOC do not influence hippocampal synaptic transmission in human. [Jpn J Physiol 54 Suppl:S241 (2004)]
