Department of Physiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran.
Biol Trace Elem Res. 2018 Sep;185(1):143-147. doi: 10.1007/s12011-017-1234-5. Epub 2018 Jan 15.
Previous studies have shown the inhibitory effect of the in vitro application of copper sulfate on hippocampal long-term potentiation. While in vivo administration of copper did not affect spatial learning and memory. To find possible answers to this controversial issue, we evaluate the effect of different doses of copper sulfate on in vivo long-term potentiation, synaptic transmission, and paired-pulse behavior of CA1 pyramidal cells. Thirty-two male Wistar rats were divided into four groups: control, 5, 10, and 15 mg of copper sulfate. Field excitatory postsynaptic potential from the stratum radiatum of CA1 neurons was recorded following Schaffer collateral stimulation in rats. Spike amplitude, long-term potentiation and paired-pulse index were measured in all groups. The results of this study showed that 5 mg/kg copper sulfate increased synaptic transmission and inhibited long-term potentiation and decreased the hippocampal paired-pulse ratio, while 10 and 15 mg/kg copper sulfate did not affect CA1 synaptic transmission properties. Low, but not high, doses of copper sulfate affect synaptic plasticity. This finding may explain the difference between the effect of copper on synaptic plasticity and spatial learning and memory.
先前的研究表明，体外应用硫酸铜对海马长时程增强具有抑制作用。而体内给予铜则不会影响空间学习和记忆。为了找到这个有争议问题的可能答案，我们评估了不同剂量硫酸铜对体内长时程增强、突触传递和 CA1 锥体神经元成对脉冲行为的影响。将 32 只雄性 Wistar 大鼠分为四组：对照组、5mg/kg、10mg/kg 和 15mg/kg 硫酸铜组。在大鼠中，通过 Schaffer 侧支刺激记录来自 CA1 神经元放射状层的场兴奋性突触后电位。在所有组中测量尖峰幅度、长时程增强和成对脉冲指数。这项研究的结果表明，5mg/kg 硫酸铜增加了突触传递，抑制了长时程增强，降低了海马的成对脉冲比，而 10mg/kg 和 15mg/kg 硫酸铜则不影响 CA1 突触传递特性。低剂量但不是高剂量的硫酸铜会影响突触可塑性。这一发现可能解释了铜对突触可塑性和空间学习记忆影响的差异。
