Bunnett N W, Helton W S, Debas H T, Ensinck J W
Department of Surgery, University of California, San Francisco 94143.
Am J Physiol. 1990 Feb;258(2 Pt 1):G316-9. doi: 10.1152/ajpgi.1990.258.2.G316.
Calcitonin gene-related peptide (CGRP) stimulates release of peptides derived from pro-somatostatin (Pro-S) into the general circulation. The purpose of this investigation was to elucidate the origin and molecular heterogeneity of Pro-S-derived peptides secreted in response to CGRP. Catheters were placed into the vena cava and veins draining the gastric fundus and corpus, antrum, and small intestine of anesthetized pigs. Human CGRP I was infused into the descending aorta at 0.2, 0.4, 0.8, and 1.6 micrograms.kg-1.h-1 for consecutive 30-min intervals. Blood was collected from the venous catheters after each period. S-28 was separated from Pro-S, S-14, and S-13 by immunoaffinity chromatography and peptides were quantified by radioimmunoassay. CGRP primarily evoked release of peptides measured collectively as Pro-S, S-14, and S-13 into venous blood draining the fundus and corpus, and concentrations were significantly elevated above basal at 0.8 and 1.6 micrograms.kg-1.h-1 CGRP (P less than 0.05). Basal concentrations of S-28, Pro-S, S-14, and S-13 in blood from the antrum and small intestine were not significantly elevated by CGRP. In conclusion, CGRP stimulated release of Pro-S-derived peptides from the gastric fundus and corpus but not from the antrum or small intestine.
降钙素基因相关肽（CGRP）可刺激源自前生长抑素（Pro-S）的肽类释放进入体循环。本研究的目的是阐明响应CGRP分泌的Pro-S衍生肽的来源和分子异质性。将导管插入麻醉猪的腔静脉以及引流胃底、胃体、胃窦和小肠的静脉中。以0.2、0.4、0.8和1.6微克·千克⁻¹·小时⁻¹的剂量，连续30分钟将人CGRP I注入降主动脉。每个时间段后从静脉导管采集血液。通过免疫亲和色谱法从Pro-S、S-14和S-13中分离出S-28，并通过放射免疫测定法定量肽类。CGRP主要引起以Pro-S、S-14和S-13共同测量的肽类释放到引流胃底和胃体的静脉血中，在CGRP剂量为0.8和1.6微克·千克⁻¹·小时⁻¹时，浓度显著高于基础水平（P<0.05）。CGRP未使胃窦和小肠血液中S-28、Pro-S、S-14和S-13的基础浓度显著升高。总之，CGRP刺激胃底和胃体释放Pro-S衍生肽，但不刺激胃窦或小肠释放。
