Laboratorio de Magnetobiología, Departamento de Anatomía e Histología, Facultad de Medicina, Universidad de Zaragoza, 50009 Zaragoza, Spain.
Comp Biochem Physiol A Mol Integr Physiol. 2013 Dec;166(4):603-18. doi: 10.1016/j.cbpa.2013.08.012. Epub 2013 Sep 3.
Pairs of Helix aspersa neurons show an alternating magnetic field dependent frequency synchronization (AMFS) when exposed to a weak (amplitude B0 between 0.2 and 150 Gauss (G)) alternating magnetic field (AMF) of extremely low frequency (ELF, fM = 50 Hz). We have compared the AMFS patterns of discharge with: i) the synaptic activity promoted by glutamate and acetylcholine; ii) the activity induced by caffeine; iii) the bioelectric activity induced on neurons interconnected by electric synapses. AMFS activity reveals several specific features: i) a tight coincidence in time of the pattern and frequency, f, of discharge; ii) it is induced in the time interval of field application; iii) it is dependent on the intensity of the sinusoidal applied magnetic field; iv) elicited biphasic responses (excitation followed by inhibition) run in parallel for the pair of neurons; and v) some neuron pairs either spontaneously or AMF synchronized can be desynchronized under applied higher AMF. Our electron microscopy studies reveal gap-like junctions confirming our immunocytochemistry results about expression of connexin 26 (Cx26) in 4.7% of Helix neurons. AMF and carbenoxolone did not induce any significant effect on spontaneous synchronization through electric synapses.
当暴露于弱（幅度 B0 在 0.2 到 150 高斯（G）之间）极低频（ELF，fM = 50 Hz）的交变磁场（AMF）时，双螺旋蜗牛神经元表现出磁场依赖的频率同步（AMFS）。我们比较了放电的 AMFS 模式与：i）谷氨酸和乙酰胆碱促进的突触活动；ii）咖啡因诱导的活动；iii）电突触连接的神经元诱导的生物电活动。AMFS 活动显示出几个特定的特征：i）放电模式和频率 f 之间的时间紧密一致；ii）它是在磁场施加的时间间隔内诱导的；iii）它依赖于正弦施加磁场的强度；iv）诱发的双相反应（兴奋后抑制）在神经元对中平行运行；v）一些神经元对要么自发地，要么通过 AMF 同步，可以在施加更高的 AMF 下失步。我们的电子显微镜研究揭示了缝隙连接，证实了我们关于 Cx26 在 4.7%的螺旋神经元中表达的免疫细胞化学结果。AMF 和 carbenoxolone 不会通过电突触对自发同步产生任何显著影响。
