Protective Effects of Gastrodin on Lead-Induced Synaptic Plasticity Deficits in Rat Hippocampus

Abstract

Lead is a well-known toxin in the environment that causes severe damage to the nervous system. Gastrodin is the main bioactive component of Tian ma (Gastrodia elata Bl.), which is a traditional herbal medicine widely used in eastern Asia. Increasing lines of evidence show that gastrodin has diverse effects, especially neuroprotective effects. In the present study, we investigated whether gastrodin supplementation can rescue impairments of synaptic plasticity produced by developmental lead exposure. We examined three electrophysiological parameters of synaptic plasticity: input/output (I/O) function, paired-pulse facilitation (PPF), and long-term potentiation (LTP) of field excitatory postsynaptic potential (fEPSP) in the hippocampal CA1 region of rats on postnatal day 22 (P22). Our results showed that lead exposure significantly impaired synaptic plasticity in the hippocampal CA1 region and that gastrodin can effectively rescue these lead-induced impairments. Therefore, gastrodin may have potential therapeutic value for lead-induced impairments during human developmental stages.

Key words

Gastrodia elata - Orchidaceae - gastrodin - lead - synaptic plasticity - rat

References

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