RUI: Ontogeny of Frequency-dependent Hippocampal Synaptic Plasticity in Freely Moving Rat

0074530 Bronzino本研究的目的是检验一个主要假设，即在出生后早期发育过程中，在与学习和记忆密切相关的脑结构中，特定神经元回路（海马三突触回路的第一支）的突触可塑性发生了显著变化。已经表明，海马回路对传入输入的反应根据输入的频率和模式而变化。对海马传入输入的某些激活模式的响应可导致海马突触响应的增强（长时程增强（LTP））或减弱（长时程抑制（LTD））。长时程增强和长时程抑制现象已在成年动物中得到广泛研究，但很少有研究检查了这种神经可塑性反应的发育起始和成熟，这些研究通常是在体外切片或麻醉制剂中进行的。没有这样的发展研究已经进行了行为的动物，因此，进行的研究是独一无二的，在这方面，该项目的主要目标是应用最近开发的手术和记录技术，以量化的个体发育的频率依赖性反应的穿孔路径/齿状颗粒细胞突触在断奶前，自由移动的雄性大鼠。

0074530BronzinoThe objective of this research is to test a major hypothesis that there are significant changes, during early postnatal development, in synaptic plasticity in a specific neuronal circuit, the first limb of the hippocampal trisynaptic circuit, in a brain structure intimately involved in learning and memory. It has been shown that hippocampal circuit responses to afferent input vary depending upon the frequency and pattern of the input. The response to certain patterns of activation of hippocampal afferent inputs may result in either enhancement (long-term potentiation (LTP)), or a diminishment (long-term depression (LTD)) of the hippocampal synaptic response. The phenomena of long-term potentiation and long-term depression have been extensively studied in adult animals, but the few studies which have examined the developmental onset and maturation of such neuroplastic responses have generally been carried out in vitro slice or anesthetized preparations. No such developmental study has been carried out in behaving animals; hence, the studies to be conducted are unique in this regard.The major goal for the project is to apply recently developed surgical and recording techniques to quantify the ontogeny of frequency-dependent responses of the perforant path/dentate granule cell synapse in pre-weaning, freely moving male rats.