抄録
The effects of the type of prepulse (PP: visual 30ms and auditory 30ms) and lead time (50, 100, 200ms) on the acoustic startle inhibition (prepulse inhibition: PPI) were tested and compared among four strains of inbred mice (BALB/cA, C3H/HeJ, C57BL/6J, and DBA/2N: all n=11). Following 40 trials of habituation using single pulse (white noise: P; 115dB, 50ms), the prepulse session made of 36 trials was conducted. In the habituation, the startle amplitude and peak latency were measured. DBA mice showed weaker startle amplitude than the other 3 strains. The peak latency of the BALB mice was faster than the other strains. The PPI by auditory PP was largest in C57BL, followed by C3H, and the least in BALB mice. DBA mice showed no PPI effect. The PPI under visual prepulse condition was observed only in BALB strain. Contrary, DBA mice showed prepulse facilitation in the 50ms lead time condition.
