P. Igelmund et al., HIBERNATION-RELATED MODIFICATION OF ACTIVITY-DEPENDENT PROPERTIES OF SYNAPTIC TRANSMISSION IN HAMSTER HIPPOCAMPUS, Neuroscience research communications, 13(3), 1993, pp. 167-173
In order to reveal hibernation-related modifications in the cold resis
tance of neuronal function, we measured the temperature below which st
imulus-evoked synaptic transmission was blocked (threshold temperature
) in area CA1 of hippocampal slices from warm-acclimated golden hamste
rs, from hibernating golden hamsters, and from rats. The threshold tem
peratures were separately analyzed for the first and the second respon
se evoked by paired-pulse stimulation (pulse interval 50 ms). 1. In sl
ices from golden hamsters the threshold temperatures for evoked synapt
ic transmission were at about 17-degrees-C, which is 2 - 3-degrees-C h
igher than in rat slices. This indicates that hippocampal function at
lower temperatures than in nonhibernators is not a prerequisite for hi
bernation. 2. In slices from hibernating hamsters, the threshold tempe
rature for the second response in the paired-pulse stimulation was sig
nificantly lower than in slices from warm-acclimated hamsters. For the
first response, in contrast, the difference was not significant. This
indicates a hibernation-related modification of activity-dependent ne
uronal processes.