The Center for Neuroscience at the University of Pittsburgh, PA 15213, USA.
J Neurophysiol. 2011 Oct;106(4):1662-8. doi: 10.1152/jn.00196.2011. Epub 2011 Jul 13.
Approximately 20% of the adult population suffers from migraine. This debilitating pain disorder is three times more prevalent in women than in men. To begin to evaluate the underlying mechanisms that may contribute to this sex difference, we tested the hypothesis that there is a sex difference in the inflammatory mediator (IM)-induced sensitization of dural afferents. Acutely dissociated retrogradely labeled dural afferents from adult Sprague-Dawley rats were examined with whole cell patch-clamp recordings. Baseline passive and active electrophysiological properties of dural afferents from both sexes were comparable. However, while IM-induced increases in the excitability of dural afferents from male and female rats were also comparable, the proportion of dural afferents from female rats sensitized by IM (100%) was significantly greater than that of dural afferents from male rats (50%). This appeared to be due to differences downstream of IM receptors, as tetrodotoxin-resistant sodium current was increased by IM in a majority of male dural afferents (13/14). These data indicate that there are both quantitative and qualitative differences in the IM-induced sensitization of dural afferents that may contribute to the sex difference in the manifestation of migraine.
大约 20%的成年人患有偏头痛。这种使人虚弱的疼痛障碍在女性中的发病率是男性的三倍。为了开始评估可能导致这种性别差异的潜在机制，我们检验了这样一个假设，即炎症介质（IM）诱导的硬脑膜传入神经敏化存在性别差异。我们用全细胞膜片钳记录技术检测了成年 Sprague-Dawley 大鼠急性分离的逆行标记的硬脑膜传入神经。两性硬脑膜传入神经的基线被动和主动电生理特性相当。然而，尽管 IM 诱导的雄性和雌性大鼠硬脑膜传入神经兴奋性增加相当，但 IM 致敏的雌性大鼠硬脑膜传入神经的比例（100%）明显高于雄性大鼠（50%）。这似乎是由于 IM 受体下游的差异所致，因为 IM 增加了大多数雄性硬脑膜传入神经（13/14）的河豚毒素抗性钠电流。这些数据表明，IM 诱导的硬脑膜传入神经敏化存在数量和质量上的差异，这可能导致偏头痛表现的性别差异。
