摘要
本实验采用放射配体结合分析研究了脊髓内有无胰高血糖素受体。结果显示,在大鼠脊髓内含有较丰富的^(125)Ⅱ-胰高血糖素的特异性结合位点;且胸、腰段脊髓内特异性位点的结合量无明显差别;比较脊髓前、后部特异性位点的结合量,发现脊髓后半部”^(125)Ⅱ-胰高血糖素的特异性结合量明显较前半部为高;且非标记胰高血糖素可竞争性地与^(125)Ⅱ-胰高血糖素的特异性结合位点结合,其50%抑制剂量(IC_(50))约为0.5 nmol/L。
The bindings of radiolabeled glucagon to rat spinal cord membranes were investigated.The results showed that high specific bindings of ^(125)I-glucagon distributed in the thoracic and lumbosacral spinal cord.The specific bindings were greater to dorsal part relative to ventral part of the spinal cord.Native unlabeled glucagon was able to compete with ^(125)I-glucagon bindings to rat spinal cord homogenate. Glucagon(0.5 nmol/L)was required for half-maximal displacement(IC_(50)).These findings provide first evidence f(?)r glucagon receptor binding sites in rat spinal cord and they suggest that glucagon may play a role in modulationg both sensory and motet functions in spinal cord as a neurotransmitter or neuromodulator.
关键词
高血糖素
生理学
脊髓
受体
MeSH glucagon/PH
islands of Langerhans/PH
spinal cord/AH
rats
animals,laboratory
