Effect of protein transduction domain-brain derived neurotrophic factor on Na⁺, Ca²⁺, K⁺ channels of hippocampal neurons

Objective To study the effects of protein transduction domain（PTD）-brain derived neurotrophic factor （BDNF） on Na+, Ca2+, and K+ channels on rat hippocampus neurons. Methods Voltage-dependent currents of Na+, Ca2+, and K+ channels in cultured rat hippocampal neurons were recorded using the whole-cell patch-clamp technique. Effect of PTD-BDNF on the current of Na+, Ca2+, and K+ channels was observed. Results Compared with the control group, the peak amplitude of PTD-BDNF and BDNF increased 39.35% and 41.99%, respectively, making the curve of Na+ current sweep down（n=4, P＜0.01）. The peak amplitude of hippocampus neurons increased 39.20% and 38.72% , respectively, making the curve of Ca2+ current sweep down（n=4, P＜0.01）. Compared with the control group, at the stimulant voltage of 20mV, the peak amplitude of PTD-BDNF and BDNF decreased 29.30%, 28.06% and 29.76%, 33.38%, making curve of K+ current sweep down（n=4, P＜0.01）. There was no difference in effect of PTD-BDNF and BDNF, P＞0.05. Conclusion PTD-BDNF and BDNF have similar modulation effects on voltage-dependent ion channels, and share a similar molecular basis in resting membrane potential of neurons and nervous excitation.