降钙素基因相关肽防治内皮素-1致新生鼠肺出血的实验研究

The preventive and therapeutical effect of calcitonin gene related peptide on pulmonary hemorrhage induced by edothelin-1 in newborn rats

目的观察外源性降钙素基因相关肽（CGRP）防治内皮素（ET）-1致肺出血的作用。方法（1）新生Wistar大鼠50只，随机分为对照组A组10只，实验组B、C、D、E组各10只。A组经气管插管内给予生理盐水30μl实验组给予4×10^-6mol／L的外源性ET-1 30μl半小时后，C、D、E组分别经气管插管内给予6．7×10^-8、6．7×10^-7、6．7×10^-6mol／L的外源性CGRP20μl，了解其对肺出血的治疗作用。（2）新生Wistar大鼠40只，随机分为对照组F组10只，实验组G、H、I组各10只。F组经气管插管内给予生理盐水20以，实验组分别给予6．7×10^-8、6．7×10^-7、6．7×10^-6mol／L的外源性CGRP20μl，1h后各组经气管插管内给予外源性ET-130μl，了解CGRP对肺出血的预防作用。各组大鼠处死后，获取肺组织，观察大体病理改变。结果（1）气道内滴入ET-1后再滴入不同浓度CGRP，可减轻ET-1致肺出血，其中6．7×10^-6mol／L给药浓度效果最佳。（2）经CGRP预处理后再滴入ET-1，肺组织损伤程度减轻。结论外源性CGRP有拮抗ET-1致肺出血的作用。

Objective To investigate the preventive and therapeutical effect of exogenous calcitonin gene related peptide （CGRP） on pulmonary hemorrhage induced by endothelin-1 （ET-1） in newborn rats.Methods （1） To study the therapeutical effect of CGRP on pulmonary hemorrhage induced by ET-1 ： 50 newborn Wistar rats were randomly assigned to receive intratracheal injection of 30μl normal saline （group A,n = 10） and 30/A 4 ×10^-6 mol/L exogenous ET-1 （group B, C, D and E, n = 10） .After 30 minutes, the rats in group B, C, D and E were intratracheally injected with 20 /A exogenous CGRP of different concentration from 6.7 ×10^-8 to 6.7 ×10^-6 mol/L. Three hours after the latest injection, the rats in group A- E were sacrifled. （2） To study the preventive effect of CGRP on pulmonary hemorrhage： 40 newborn Wistar rats were randomly assigned to receive intratracheal injection of 20 μl normal saline （group F, n = 10）and 20μl exogenousCGRP of different concentrations from 6.7 ×10^- 8 to 6.7 ×10^- 6 mol / L （ group G, H and I, n = 10 ） .After 60 minutes, the rats in group F- I were intratracheally injected with 30μl 4×10^-6 mol/L exogenous ET-1 and sacrified 2 hours later. The lungs of rats were obtained for pathological exrnination. Results （ 1 ） After administration of different concentrations of exogenous CGRP, the incidence of pulmonary hemorrhage was decreased, the best protective effect was observed with the concentration of 6.7 ×10^- 6 mol/L. （2） the degree of lung injury were attenuated by CGRP pretreatment. Conclusion The exogenous CGRP can inhibit pulmonary hemorrhage induced by ET-1.