Abstract: | Incubation of the rat hippocampal slices with caspase-3 inhibitor Z-DEVD-FMK resulted in a time-dependent decrease in long-term potentiation (LTP) magnitude. Analysis of paired pulse facilitation at a 70-msec interval revealed that, after caspase-3 inhibition, the increase in the amplitude of the second response in the pair during LTP that was characteristic for control slices, did not occur. In this situation, the LTP magnitude depended on differences in the amplitudes of the first and second responses before the LTP induction. LTP was absent in slices with initially high efficacy of the afferent stimulation and respective low paired pulse facilitation. The Caspase inhibition seems to prevent structural reorganization during the LTP related to involvement into the response of new synapses and neurons. |