Effect of repeated electroconvulsive shocks (ECS) on subthreshold doses of some CNS stimulants.

The effect of chronic application of electroconvulsive shocks (ECS) on the time of onset of convulsions and percentage of mice convulsed by the centrally acting drugs picrotoxin and pentylenetetrazol (PTZ) was studied in mice. There was a significant decrease in time to onset of convulsions in the ECS group following PTZ but not after picrotoxin. However, mortality was significantly increased following administration of either drugs after ECS pretreatment. The results support the hypothesis of ECS increasing either postsynaptic sensitivity or neuronal sensitivity.