Chijiiwa Y, Kabemura T, Misawa T, Kawakami O, Nawata H
Third Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Life Sci. 1992;50(21):1615-23. doi: 10.1016/0024-3205(92)90447-w.
Smooth muscle cells isolated from the gastric muscle layers of the guinea pig were used to determine whether calcitonin gene-related peptide (CGRP) and atrial natriuretic peptide (ANP) can inhibit the contractile response produced by 10(-6) M carbachol by exerting a direct action on muscle cells. In addition, the inhibitory effect of 2', 5'-dideoxyadenosine, an inhibitor of adenylate cyclase, on the CGRP-induced or ANP-induced relaxation of gastric smooth muscle cells were examined. CGRP and ANP inhibited the contractile response produced by carbachol in a dose-dependent manner, and the values of IC50 were 3 nM and 2 nM, respectively. 2',5'-dideoxyadenosine significantly inhibited the relaxation produced by CGRP. On the other hand, 2',5'-dideoxyadenosine did not have any significant effect on the relaxation produced by ANP. These results demonstrate the difference between intracellular mechanism responsible for gastric smooth muscle relaxation by CGRP and the mechanism responsible for muscle relaxation by ANP, and strongly suggest that the action of CGRP is mediated by adenosine 3',5'-cyclic monophosphate.
从豚鼠胃肌层分离出的平滑肌细胞被用于确定降钙素基因相关肽（CGRP）和心钠素（ANP）是否能通过对肌细胞产生直接作用来抑制由10⁻⁶M卡巴胆碱引起的收缩反应。此外，还研究了腺苷酸环化酶抑制剂2',5'-二脱氧腺苷对CGRP诱导或ANP诱导的胃平滑肌细胞舒张的抑制作用。CGRP和ANP以剂量依赖性方式抑制卡巴胆碱产生的收缩反应，IC50值分别为3 nM和2 nM。2',5'-二脱氧腺苷显著抑制CGRP产生的舒张。另一方面，2',5'-二脱氧腺苷对ANP产生的舒张没有任何显著影响。这些结果证明了CGRP引起胃平滑肌舒张的细胞内机制与ANP引起肌肉舒张的机制之间的差异，并强烈表明CGRP的作用是由3',5'-环磷酸腺苷介导的。
