K. Morimoto et al., TIME-DEPENDENT CHANGES IN RAT HIPPOCAMPAL SYNAPSIN-I MESSENGER-RNA EXPRESSION DURING LONG-TERM POTENTIATION, Brain research, 783(1), 1998, pp. 57-62
We studied the time-dependent changes in synapsin I mRNA levels after
hippocampal long-term potentiation (LTP) in rats in vivo. Following LT
P induction by stimulating the perforant path, synapsin I mRNA express
ion in the granule cell layer of the dentate gyrus ipsilateral to stim
ulation increased significantly in a time-dependent manner. From 2 to
8 h after stimulation, the synapsin I mRNA levels in the ipsilateral d
entate gyrus were significantly higher than those of controls subjecte
d to a sham procedure. The synapsin I mRNA level (157.4 +/- 7.1% of th
e control level, mean +/- SEM) was at a maximum 8 h after stimulation.
The synapsin I mRNA level of animals that received only test pulses d
id not increase significantly, compared with the control level. These
results suggest that the increased level of synapsin I mRNA is related
to persistent enhancement of synaptic activity within the neural netw
orks in which dentate granule cells participate in LTP. (C) 1998 Elsev
ier Science B.V.