Mulderry P K, Ghatei M A, Spokes R A, Jones P M, Pierson A M, Hamid Q A, Kanse S, Amara S G, Burrin J M, Legon S
Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, U.K.
Neuroscience. 1988 Apr;25(1):195-205. doi: 10.1016/0306-4522(88)90018-8.
Expression of the calcitonin gene-related peptide, alpha-calcitonin gene-related peptide (CGRP), and the homologous beta-CGRP were compared in sensory and enteric nerves of the rat. Analysis of CGRP-like immunoreactivity by cation exchange chromatography and radioimmunoassay showed that in the dorsal root ganglia, dorsal spinal cord and in those peripheral tissues where CGRP-like immunoreactivity is primarily localized to sensory fibres, alpha-CGRP concentrations were three to six times greater than beta-CGRP concentrations. In the intestine, however, beta-CGRP concentrations were up to seven times greater than alpha-CGRP concentrations. Only beta-CGRP was detected in the intestines of capsaicin-treated rats. Northern blot and in situ hybridization to alpha-CGRP- and beta-CGRP-specific probes showed that while both alpha-CGRP and beta-CGRP messenger ribonucleic acids occurred in the dorsal root ganglia, only beta-CGRP messenger ribonucleic acid occurred in the intestine, where it was localized to enteric neurons. Receptor binding sites on membranes of rat heart and colon had approximately equal affinities for alpha-CGRP and beta-CGRP. The two peptides were equipotent in increasing the rate and force of atrial contractions but alpha-CGRP was slightly (2.6 times) more potent than beta-CGRP in relaxing colonic smooth muscle. Thus, both alpha-CGRP and beta-CGRP occur in the rat nervous system and are both biologically active. Sensory neurons and enteric neurons have been identified as populations which preferentially express alpha-CGRP and beta-CGRP, respectively.
在大鼠的感觉神经和肠神经中，对降钙素基因相关肽、α-降钙素基因相关肽（CGRP）和同源的β-CGRP的表达进行了比较。通过阳离子交换色谱法和放射免疫分析法对CGRP样免疫反应性进行分析，结果显示，在背根神经节、脊髓背侧以及那些CGRP样免疫反应性主要定位于感觉纤维的外周组织中，α-CGRP的浓度比β-CGRP的浓度高3至6倍。然而，在肠道中，β-CGRP的浓度比α-CGRP的浓度高7倍之多。在辣椒素处理的大鼠肠道中仅检测到β-CGRP。用α-CGRP和β-CGRP特异性探针进行的Northern印迹和原位杂交显示，虽然α-CGRP和β-CGRP信使核糖核酸均存在于背根神经节中，但只有β-CGRP信使核糖核酸存在于肠道中，且定位于肠神经元。大鼠心脏和结肠膜上的受体结合位点对α-CGRP和β-CGRP具有大致相等的亲和力。这两种肽在增加心房收缩的速率和力量方面具有同等效力，但在舒张结肠平滑肌方面，α-CGRP的效力略强（2.6倍）于β-CGRP。因此，α-CGRP和β-CGRP均存在于大鼠神经系统中且都具有生物活性。感觉神经元和肠神经元已被确定为分别优先表达α-CGRP和β-CGRP的细胞群体。
