Bunnemann B, Fuxe K, Ganten D
Department of Histology and Neurobiology, Karolinska Institute, Stockholm, Sweden.
J Cardiovasc Pharmacol. 1992;19 Suppl 6:S51-62. doi: 10.1097/00005344-199219006-00010.
This report summarizes the present data about the existence of components of the renin-angiotensin system in the rat brain. Angiotensinogen mRNA, mas proto-oncogene mRNA, angiotensin II (Ang II), and Ang II receptors have been mapped in the brain by using in situ hybridization, immunocytochemistry, and receptor autoradiography. These markers turned out to be widely distributed throughout the brain and to be not only restricted to areas related to cardiovascular control, but also to be present in functionally different areas, suggesting also other functions of angiotensin peptides. The distribution patterns of these components were correlated with data on the distribution of angiotensinogen, renin, angiotensin converting enzyme, and angiotensin fragments that revealed substantial topological mismatches. Using the model of "volume transmission," possible explanations for these mismatches are proposed. In this regard, a possible involvement of angiotensin fragments and the mas proto-oncogene in the functioning of the brain renin-angiotensin system is also discussed, demonstrating the increasing complexity of this central regulatory system.
本报告总结了目前有关大鼠脑中肾素 - 血管紧张素系统各成分存在情况的数据。通过原位杂交、免疫细胞化学和受体放射自显影技术，已在脑中绘制出血管紧张素原mRNA、mas原癌基因mRNA、血管紧张素II（Ang II）和Ang II受体的分布图。结果表明，这些标志物广泛分布于整个大脑，不仅局限于与心血管控制相关的区域，还存在于功能不同的区域，这也提示了血管紧张素肽的其他功能。这些成分的分布模式与血管紧张素原、肾素、血管紧张素转换酶和血管紧张素片段的分布数据相关，这些数据显示出明显的拓扑不匹配。利用“容积传递”模型，对这些不匹配现象提出了可能的解释。在这方面，还讨论了血管紧张素片段和mas原癌基因可能参与脑肾素 - 血管紧张素系统功能的情况，这表明该中枢调节系统的复杂性日益增加。
