Nahin Richard L, Hylden Janice L K, Humphrey Emma
Neurobiology and Anesthesiology Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, MD 20892 USA.
Pain. 1992 Nov;51(2):135-143. doi: 10.1016/0304-3959(92)90254-9.
Using a double-labeling technique, we evaluated the input of afferents immunoreactive for dynorphin peptide onto a population of lumbar spinal neurons contributing to the spinoparabrachial tract in rats with 1 inflamed hind paw. We found that the frequency and distribution with which dynorphin immunoreactive varicosities were in apposition to projection neurons varied according to neuron location. In particular, neurons in the superficial dorsal horn and neck of the dorsal horn receive a high degree of dynorphin input. We also determine that unilateral peripheral inflammation is associated with both an increase in the number of projection neurons receiving detectable DYN input and in the frequency of this input onto a given neuron, with the largest increase seen in the superficial dorsal horn. Since almost all superficial dorsal horn neurons contributing to the spinoparabrachial tract respond either exclusively or maximally to noxious stimulation, our data supports dynorphin's involvement in nociception.
运用双标记技术，我们评估了在一侧后爪发炎的大鼠中，对强啡肽肽免疫反应阳性的传入纤维向一群构成脊髓臂旁束的腰段脊髓神经元的投射。我们发现，强啡肽免疫反应阳性的膨体与投射神经元并列存在的频率和分布因神经元位置而异。特别是，浅背角和背角颈部的神经元接受大量的强啡肽输入。我们还确定，单侧外周炎症与接受可检测到的强啡肽输入的投射神经元数量增加以及该输入作用于单个神经元的频率增加有关，其中浅背角的增加最为显著。由于几乎所有构成脊髓臂旁束的浅背角神经元对伤害性刺激仅产生唯一反应或最大反应，我们的数据支持强啡肽参与伤害感受。
