Tenconi B, Donadoni L, Germani E, Bertelli A, Mantegazza P, Di Giulio A M, Ramacci M T, Gorio A
Department of Medical Pharmacology, School of Medicine, University of Milan, Italy.
Int J Clin Pharmacol Res. 1992;12(5-6):263-7.
Peripheral nerve lesions cause retrograde changes in the spinal cord, involving initially the descending serotoninergic pathways and later the substance P sensory input and methionine-enkephalin interneurons. Within 48 h after sciatic nerve resection there is a significant increase of 5-hydroxyindoleacetic acid in the lumbar spinal cord with no changes of serotonin metabolism in the cell body areas. The immunocytochemical analysis of the spinal cord shows that 20 days after nerve lesion there is a loss of substance P-positive boutons in the laminae I and II of the dorsal horn in the lumbar segment. Such a morphological change is correlated by radioimmunoassay for substance P and methionine-enkephalin, that reveals a significant loss of both peptides. Treatment with acetyl-L-carnitine prevents the early 5-hydroxyindoleacetic acid increase and the reduction of peptide content observed 20 days after lesioning the sciatic nerve. These data suggest that treatment with acetyl-L-carnitine exerts a neuroprotective activity preventing the retrograde changes triggered by peripheral nerve lesions.
周围神经损伤会导致脊髓发生逆行性改变，最初涉及下行5-羟色胺能通路，随后涉及P物质感觉输入和甲硫氨酸脑啡肽中间神经元。坐骨神经切除术后48小时内，腰段脊髓中5-羟吲哚乙酸显著增加，而细胞体区域的5-羟色胺代谢无变化。脊髓的免疫细胞化学分析表明，神经损伤20天后，腰段背角I层和II层中P物质阳性终扣减少。这种形态学变化与P物质和甲硫氨酸脑啡肽的放射免疫分析结果相关，该分析显示这两种肽均显著减少。乙酰-L-肉碱治疗可预防坐骨神经损伤后早期5-羟吲哚乙酸的增加以及损伤20天后观察到的肽含量减少。这些数据表明，乙酰-L-肉碱治疗具有神经保护活性，可防止周围神经损伤引发的逆行性改变。
