犬心脏表面主要神经丛降钙素基因相关肽和P物质的免疫组织化学研究

目的 探明犬心脏表面神经丛的化学特性。方法 免疫组织化学ABC法。结果 在犬心脏表面各神经丛均见降钙素基因相关肽(CGRP)免疫反应阳性神经元，而SP免疫阳性神经元仅在心房背侧神经丛(DAP)、房间隔神经丛(IAP)和主动脉．肺动脉间神经丛(A—PP)内见到。CGRP—IR和SP—IR神经元形态、大小相似。心房表面神经丛内的CGRP—IR和SP—IR神经元都较心室表面神经丛者多。在心脏表面各脂肪垫及心肌间隙等处见到多量CGRP-IR、SP—IR神经纤维，多靠近血管或附于血管壁，在一些部位可见这两种肽能神经纤维似与心肌细胞接触。结论犬心脏表面神经丛内存在CGRP和SP；其在心脏内执行的功能可能有联系或相似之处，但也有不同；两种肽能神经对心房和心室的支配不对称，提示CGRP和SP可能直接参与心肌细胞和心脏血管活动的调控。

IMMUNOHISTOCHEMICAL RESEARCH ON CGRP AND SP IN THE CANINE MAIN SUPERFICIAL CARDIAC PLEXUS

Objective To investigate the chemical properties of superficial cardiac neurons. Methods By means of immunohistochemical ABC technique,the study was performed concerning the distribution of calcitonin gene-related peptide(CGRP) and substance P(SP) in the canine main cardiac superficial plexus. Results CGRP-immunoreactive(IR) neurons were found in every plexus,but SP-IR neurons could be observed only in dorsal atria plexus(DAP),inter atria plexus(IAP) and aorta-pulmonary plexus(A-PP).The shape and size of CGRP-IR and SP-IR neurons were similar.The comparative study on atria and ventricles indicated that CGRP-IR and SP-IR neurons in atria were more than those in ventricles.Numerous CGRP-IR,SP-IR nerve fibers could be observed in each fat pats and intermyocardiocytes.These nerve fibers were usually situated near blood vessels,or were attached to vessel wall.Somewhat CGRP-IR and SP-IR nerve fibers were connected with myocardiocytes in some regions.Conclusion The results indicated that actually existed two peptides in canine cardiac superficial plexus.These implied that the regulations of the two kinds of peptidergic neurons to atria and ventricle were different.The two kinds of neurons mentioned above were likely to perform different or similar functions in canine heart.CGRP and SP could possibly modulate the activities of myocardiocytes and vessels of heart directly.