自发性高血压大鼠脑内NPY阳性神经纤维的变化

【目的】观察自发性高血压大鼠(spontaneously hypertension rat,SHR)血压升高之后,脑内神经肽Y(neuropeptide Y,NPY)阳性神经元和纤维分布和密度变化。【方法】成年SHR(5月龄)和同龄正常血压对照组大鼠(京都Wistar,Wistar-KYOTO,WKY)各20只,雌雄不限。取脑后行冠状位连续冰冻切片,免疫组化SP法染色,用计算机图像分析系统观测NPY阳性神经元/纤维的分布与密度,并测量其平均灰度,作统计处理。【结果】两组大鼠脑内均有广泛而丰富的NPY纤维和稀疏的神经元分布。SHR组大脑皮质、下丘脑、第三脑室周围、中脑水管周围灰质、第四脑室室底灰质内的NPY阳性神经纤维密度较WKY组高,平均灰度(亮度)值低于WKY组(P<0.05)。在中脑水管、第三、第四脑室周围均有NPY纤维分布。脑组织内小血管周围有NPY纤维环形分布。【结论】成年SHR脑内多个区域NPY纤维分布增多、染色加深,提示SHR脑内NPY表达上调,对脑血管及中枢有关部位支配增强,与高血压病的发病有关。

The variations of Neuropeptide Y positive nerve fibers in the brains of SHRs

Objective] To investigate the variation of neurepeptide Y （NPY）positive fibers in brains of SHR. Methods] The adult SHR with hypertension （5 months old,n = 20）and control adult WKY （5 months old,n = 20）were used. The brain slices of 30 μm were treated by SP method of immunohistoehemistry, and were quantitatively analyzed. Results] There were abundant NPY positive fibers in the cerebral cortex, hypothalamus, periaqueduct gray, and around the third ventricle and the fourth ventricle both SHRs and WKY. The density of NPY fibers and the gray degree of NPY positive products at the above areas of SHRs were increased than WKY （ P 〈 0.05）. Conclusion ] The density of NPY positive nerve fibers in brains of adult SHR was higher than the control adult WKY. The expression of NPY was upregulated than the WKY. The innervations to cerebral arteries and cadiovascular motor centers were reinforced.