Lishnak T S, Vizzard M A
Department of Neurology, College of Medicine, University of Vermont, Burlington 05405, USA.
Auton Neurosci. 2001 Dec 10;94(1-2):62-73. doi: 10.1016/S1566-0702(01)00346-0.
These studies have demonstrated that ipsilateral renal artery occlusion (RAO) in rat results in the phosphorylation of cyclic AMP (cAMP) response element binding protein (p-CREB) in the thoracolumbar (T8-L2) spinal cord and associated dorsal root ganglia (DRG). p-CREB-immunoreactivity (IR) was expressed bilaterally in the thoracolumbar spinal cord, whereas expression in the DRG was ipsilateral relative to RAO. p-CREB-IR was primarily expressed in four distinct regions of the spinal cord: medial or lateral dorsal horn (MDH or LDH), dorsal commissural nucleus (DCN) and the region of the intermediolateral cell column (IML). After RAO, p-CREB-IR was greatest in the T13-L2 spinal segments. Within the T13-L1 spinal segments, p-CREB-IR was greatest in the MDH, LDH and DCN and expression in each of these regions was comparable within a segment. Following RAO, there was a significant (p < or = 0.001) increase in the percentage (86-98%) of p-CREB-IR spinal neurons expressing choline acetyltransferase (ChAT)-IR (a marker of preganglionic neurons) in the IML of the T10, T12 and L1 spinal segments examined. After ipsilateral RAO, expression of p-CREB-IR was increased in the ipsilateral, T8-L2 DRG with the greatest number of p-CREB-IR dorsal root ganglion cells being located in the L1 dorsal root ganglion. Retrograde tracing with Fluorogold (FG) to label renal afferent cells in the DRG revealed a significant (p < or = 0.01) increase in the percentage (75-86%) of renal afferent cells expressing p-CREB-IR after ipsilateral RAO. These studies demonstrate that p-CREB-IR is a useful tool for examining the distribution of spinal neurons and DRG involved in reflexes of renal origin. In addition, expression of p-CREB-IR may be coupled to late response genes that may exert long-term changes in neuronal function after RAO.
这些研究表明，大鼠的同侧肾动脉闭塞（RAO）会导致胸腰段（T8-L2）脊髓和相关背根神经节（DRG）中环状AMP（cAMP）反应元件结合蛋白（p-CREB）的磷酸化。p-CREB免疫反应性（IR）在胸腰段脊髓双侧表达，而在DRG中的表达相对于RAO是同侧的。p-CREB-IR主要在脊髓的四个不同区域表达：内侧或外侧背角（MDH或LDH）、背连合核（DCN）和中间外侧细胞柱（IML）区域。RAO后，p-CREB-IR在T13-L2脊髓节段中最为明显。在T13-L1脊髓节段内，p-CREB-IR在MDH、LDH和DCN中最为明显，且每个区域在一个节段内的表达相当。RAO后，在检查的T10、T12和L1脊髓节段的IML中，表达胆碱乙酰转移酶（ChAT）-IR（节前神经元的标志物）的p-CREB-IR脊髓神经元百分比显著（p≤0.001）增加（86-98%）。同侧RAO后，同侧T8-L2 DRG中p-CREB-IR的表达增加，p-CREB-IR背根神经节细胞数量最多的位于L1背根神经节。用荧光金（FG）进行逆行追踪以标记DRG中的肾传入细胞，结果显示同侧RAO后表达p-CREB-IR的肾传入细胞百分比显著（p≤0.01）增加（75-86%）。这些研究表明，p-CREB-IR是检查参与肾源性反射的脊髓神经元和DRG分布的有用工具。此外，p-CREB-IR的表达可能与晚期反应基因相关，这些基因可能在RAO后对神经元功能产生长期变化。
