Developmental onset of enduring long-term potentiation in mouse hippocampus.
Analysis of long-term potentiation (LTP) provides a powerful window into cellular mechanisms of learning and memory. Prior work shows late LTP (L-LTP), lasting >3 hr, occurs abruptly at postnatal day 12 (P12) in the stratum radiatum of rat hippocampal area CA1. The goal here was to determine the developmental profile of synaptic plasticity leading to L-LTP in the mouse hippocampus. Two mouse strains and two mutations known to affect synaptic plasticity were chosen: C57BL/6J and Fmr1-/y on the C57BL/6J background, and 129SVE and Hevin-/- (Sparcl1-/- ) on the 129SVE background. Like rats, hippocampal slices from all of the mice showed test pulse-induced depression early during development that was gradually resolved with maturation by 5 weeks. All the mouse strains showed a gradual progression between P10-P35 in the expression of short-term potentiation (STP), lasting ≤1 hr. In the 129SVE mice, L-LTP onset (>25% of slices) occurred by 3 weeks, reliable L-LTP (>50% slices) was achieved by 4 weeks, and Hevin-/- advanced this profile by 1 week. In the C57BL/6J mice, L-LTP onset occurred significantly later, over 3-4 weeks, and reliability was not achieved until 5 weeks. Although some of the Fmr1-/y mice showed L-LTP before 3 weeks, reliable L-LTP also was not achieved until 5 weeks. L-LTP onset was not advanced in any of the mouse genotypes by multiple bouts of theta-burst stimulation at 90 or 180 min intervals. These findings show important species differences in the onset of STP and L-LTP, which occur at the same age in rats but are sequentially acquired in mice.
['Ostrovskaya|Olga I|OI|0000-0002-8565-6273', 'Cao|Guan|G|', 'Eroglu|Cagla|C|', 'Harris|Kristen M|KM|0000-0002-1943-4744']
D000818:Animals D000831:Animals, Newborn D019706:Excitatory Postsynaptic Potentials D006624:Hippocampus D017774:Long-Term Potentiation D008297:Male D051379:Mice D057507:Mice, 129 Strain D008810:Mice, Inbred C57BL D018345:Mice, Knockout D008822:Mice, Transgenic D009473:Neuronal Plasticity D009924:Organ Culture Techniques D013045:Species Specificity
synaptic plasticity development maturation theta-burst potentiation