Phoenixin-14 (PNX-14) has a wide bioactivity in the central nervous system. Its role in the hypothalamus has been investigated, and it has been reported that it is involved in the regulation of excitability in hypothalamic neurons. However, its role in the regulation of excitability in entorhinal cortex and the hippocampus is unknown. In this study, we investigated whether i. PNX-14 induces any synchronous discharges or epileptiform activity and ii. PNX-14 has any effect on already initiated epileptiform discharges. We used 350 µm thick acute horizontal hippocampal–entorhinal cortex slices obtained from 30- to 35-day-old mice. Extracellular field potential recordings were evaluated in the entorhinal cortex and hippocampus CA1 region. Bath application of PNX-14 did not initiate any epileptiform activity or abnormal discharges. 4-Aminopyridine was applied to induce epileptiform activity in the slices. We found that 200 nM PNX-14 reduced the frequency of interictal-like events in both the entorhinal cortex and hippocampus CA1 region which was induced by 4-aminopyridine. Furthermore, PNX-14 led to a similar suppression in the total power of local field potentials of 1–120 Hz. The frequency or the duration of the ictal events was not affected. These results exhibited for the first time that PNX-14 has a modulatory effect on synchronized neuronal discharges which should be considered in future therapeutic approaches.

Phoenixin-14 (PNX-14) 在中枢神经系统中具有广泛的生物活性。已经研究了它在下丘脑中的作用，据报道它参与了下丘脑神经元兴奋性的调节。然而，它在调节内嗅皮层和海马兴奋性中的作用尚不清楚。在这项研究中，我们调查了 i. PNX-14 诱导任何同步放电或癫痫样活动和 ii。PNX-14 对已经开始的癫痫样放电有任何影响。我们使用了从 30 至 35 天大的小鼠获得的 350 µm 厚的急性水平海马-内嗅皮层切片。在内嗅皮层和海马 CA1 区域评估细胞外场电位记录。PNX-14 的浴应用不会引发任何癫痫样活动或异常放电。4-氨基吡啶用于诱导切片中的癫痫样活动。我们发现 200 nM PNX-14 降低了由 4-氨基吡啶诱导的内嗅皮层和海马 CA1 区域发作间期样事件的频率。此外，PNX-14 对 1-120 Hz 的局部场电位的总功率产生了类似的抑制。发作事件的频率或持续时间不受影响。这些结果首次表明 PNX-14 对同步神经元放电具有调节作用，应在未来的治疗方法中加以考虑。PNX-14 对 1-120 Hz 的局部场电位的总功率产生了类似的抑制。发作事件的频率或持续时间不受影响。这些结果首次表明 PNX-14 对同步神经元放电具有调节作用，应在未来的治疗方法中加以考虑。PNX-14 对 1-120 Hz 的局部场电位的总功率产生了类似的抑制。发作事件的频率或持续时间不受影响。这些结果首次表明 PNX-14 对同步神经元放电具有调节作用，应在未来的治疗方法中加以考虑。