Lead induced thiamine deficiency in the brain decreased the threshold of electroshock seizure in rat

Many neurological disorders that occur frequently in lead intoxicated anima ls, have also been observed in thiamine deficient animals. To test whether lead intoxication could decrease the thiamine status and thresholds of elec troshock seizure in rats, 3-week-old Wistar rats were treated with lead or lead plus thiamine. For comparison, a thiamine deficient group was included . Thiamine contents and transketolase activity, one of the thiamine depende nt enzymes in the brain regions were significantly lowered by lead intoxica tion and thiamine deficiency; In both cases, thresholds of the electroshock seizure were significantly decreased. Thiamine supplementation reversed th ese signs and decreased the brain lead concentration in the lead treated gr oup. The results from the present study suggest that the increased seizure susceptibility induced by lead intoxication in rats may be mediated at leas t in part through the changes of thiamine status. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.