Dhital K K, Gerli R, Lincoln J, Milner P, Tanganelli P, Weber G, Fruschelli C, Burnstock G
Department of Anatomy and Developmental Biology, University College London, U.K.
Brain Res. 1988 Mar 15;444(1):33-45. doi: 10.1016/0006-8993(88)90910-9.
Fluorescence and immunohistochemical techniques were used to study the pattern and density of perivascular nerves containing noradrenaline (NA) and neuropeptide Y (NPY) supplying the major cerebral arteries of 4-, 6-, 8- and 12-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar (WIS) controls. Levels of NA and NPY in the superior cervical ganglia were measured. The density of nerves containing NA and NPY was greater in the hypertensive animals at all ages studied. However, the developmental changes in the density of innervation showed similar trends in both SHR and WIS groups. With few exceptions, there was a significant increase in the density of nerves containing NA from 4 to 6 weeks and from 8 to 12 weeks of age. This was in contrast to a low expression, and in some vessels a significant decrease in the number of NPY-containing nerves from 4 to 6 weeks. The density of nerve fibres containing NPY increased significantly in almost all vessels between 6 and 8 weeks of age and then stabilized. Thus there is a differential time course for the appearance of NA and NPY during development. Furthermore, the hyperinnervation of cerebral vessels in SHR by nerves containing NA and NPY precedes the onset of hypertension and associated medial hypertrophy. High-performance liquid chromatography and enzyme-linked immunosorbant assays show that the NA and NPY contents of the superior cervical ganglion do not reflect the changes in innervation pattern seen in the terminal fibres in the cerebral arteries. This tends to support the view that a local neurovascular mechanism is involved in the maintenance of hypertension. The possibility that increase in NPY as well as NA in cerebral perivascular nerves of hypertensive animals is involved in the protection of the blood-brain barrier against oedema and cerebral haemorrhage is raised.
采用荧光和免疫组化技术研究了4周龄、6周龄、8周龄和12周龄自发性高血压大鼠（SHR）和正常血压Wistar（WIS）对照大鼠的主要脑动脉周围含去甲肾上腺素（NA）和神经肽Y（NPY）的神经分布模式和密度。测定了颈上神经节中NA和NPY的水平。在所有研究年龄段的高血压动物中，含NA和NPY的神经密度均更高。然而，SHR和WIS组的神经支配密度的发育变化呈现相似趋势。除少数例外，含NA的神经密度在4至6周龄以及8至12周龄时显著增加。这与4至6周龄时NPY含量低以及部分血管中含NPY神经数量显著减少形成对比。含NPY的神经纤维密度在6至8周龄时几乎在所有血管中显著增加，然后趋于稳定。因此，在发育过程中NA和NPY出现的时间进程存在差异。此外，含NA和NPY的神经对SHR脑血管的过度支配先于高血压及相关的中膜肥厚的发生。高效液相色谱和酶联免疫吸附测定表明，颈上神经节中的NA和NPY含量并不能反映脑动脉终末纤维中所见的神经支配模式变化。这倾向于支持局部神经血管机制参与高血压维持的观点。同时也提出了高血压动物脑周血管神经中NPY以及NA增加可能参与保护血脑屏障免受水肿和脑出血影响的可能性。
