Figure 1.

Expression of LTP in area CA1 is variable between different inbred mouse strains. The early and late phases of LTP showed significant differences in persistence in slices prepared from the four strains. One-train LTP (top) decayed more significantly at 1 hr after tetanization in the 129/SvEms strain than in the other three strains. Four-train LTP (middle) was significantly reduced 3 hr after tetanization in the CBA and 129/SvEms strains. Theta-burst LTP (bottom) was significantly attenuated at 3 hr posttetanization in all strains compared to BL/6 slices. For comparison, the same BL/6 LTP curve for each stimulation protocol is shown in each graph for the other three strains.