Neurophysiological Consequences of Acute Exposure to Methylpyridines. DYER, R. S., BURDETTE, L. J., JANSSEN, R., AND BOYES, W. K. (1985).Fundam. Appl. Toxicol.. 5,920-932. A series of neurophysiological tests was performed on Long-Evans hooded rats treated with either 2-, 3-, or 4-methylpyridine at dosages of 100 mg/kg, approximately one-half the ip LD50. The tests contained measures of sensory function (paired pulse flash evoked potentials, pattern reversal evoked potentials, and brainstem auditory evoked responses) and cerebral excitability (pentyl-enetetrazol seizures and hippocampal afterdischarges). In general, rats treated with 2- and 3-methylpyridine were more affected than those treated with 4-methylpyridine. The changes observed were in many ways similar to those seen following administration of depressant compounds: increased latency of evoked potentials and increased latency to PTZ seizures. Not all findings, however, were consistent with previously observed patterns of central nervous system depression.