Donohue S J, Stitzel R E, Head R J
Department of Pharmacology and Toxicology, West Virginia University Medical Center, Morgantown.
J Pharmacol Exp Ther. 1988 Apr;245(1):24-31.
The change in norepinephrine (NE) content with age (from 2 days to 17 weeks old) was examined in a variety of tissues from spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats. NE content was determined by either a catechol-O-methyltransferase-based radioenzymatic assay or high performance liquid chromatography with electrochemical detection. Regardless of the age of the animal, NE content per gram of tissue was significantly greater in mesenteric arteries and kidneys from SHR compared to WKY tissues, whereas NE content per whole kidney was similar between the two rat strains. The time course of enhanced NE content in caudal arteries and aortas from SHR followed the development of hypertension. In the spleen, NE content per gram of tissue was elevated in young SHR; however, in adult rats NE content was not significantly different between the two rat strains. Because spleens from WKY rats were substantially larger, total NE content per spleen was significantly greater in tissues from WKY rats. Cardiac contents of NE were similar in SHR and WKY rats at all ages examined. Adrenal epinephrine concentrations were similar in SHR and WKY rats, whereas NE content was elevated in the SHR at 46 and 81 days of age. The results of the present study demonstrate that the appearance of increased NE levels in some SHR tissues occurs before the development of hypertension in this model. If NE content is a valid index of sympathetic innervation, enhanced innervation may contribute to the vascular medial hypertrophy observed in young SHR and the elevation of blood pressure in these rats.
在自发性高血压大鼠（SHR）和正常血压的Wistar Kyoto（WKY）大鼠的多种组织中，研究了去甲肾上腺素（NE）含量随年龄（从2天到17周龄）的变化。NE含量通过基于儿茶酚-O-甲基转移酶的放射酶法或高效液相色谱电化学检测法测定。无论动物年龄如何，与WKY组织相比，SHR肠系膜动脉和肾脏中每克组织的NE含量显著更高，而两个大鼠品系全肾的NE含量相似。SHR尾动脉和主动脉中NE含量增加的时间进程与高血压的发展一致。在脾脏中，年轻SHR每克组织的NE含量升高；然而，在成年大鼠中，两个大鼠品系的NE含量没有显著差异。由于WKY大鼠的脾脏明显更大，WKY大鼠组织中每个脾脏的总NE含量显著更高。在所有检查的年龄段，SHR和WKY大鼠心脏中的NE含量相似。SHR和WKY大鼠肾上腺肾上腺素浓度相似，而在46天和81天时，SHR的NE含量升高。本研究结果表明，在该模型中，某些SHR组织中NE水平升高的现象出现在高血压发展之前。如果NE含量是交感神经支配的有效指标，那么神经支配增强可能导致年轻SHR中观察到的血管中层肥大以及这些大鼠的血压升高。
