Alexander N, Morris M
Department of Medicine, University of Southern California School of Medicine, Los Angeles 90033.
Am J Physiol. 1988 Nov;255(5 Pt 2):R768-73. doi: 10.1152/ajpregu.1988.255.5.R768.
The objective of this study was to determine whether chronic arterial baroreceptor deficit induces time-related changes in central vasopressin (AVP) and catecholamine systems. Groups of sinoaortic-denervated (SAD) and sham-operated (SO) rats were studied 1, 3, 4, 7, and 14 days after surgery. Supraoptic (SON), paraventricular (PVN) and arcuate (ARC) nuclei, median eminence (ME) region, and A1 region of medulla were obtained by micropunch from frozen brain sections and assayed for AVP, tyrosine hydroxylase (TH) activity, catecholamines, and their metabolites, dihydroxyphenylethyleneglycol (DOPEG) and 2,5-dihydroxyphenylacetic acid (DOPAC). AVP concentration in SON and PVN was increased in 1-day-SAD rats, reduced in 3- and 4-day-SAD rats, equal and above control values in 7- and 14-day-SAD rats, respectively. TH activity was increased in SON and reduced in ME and ARC of 1- and 7-day-SAD rats. In SON, DOPEG was increased, whereas in ME all catecholamines and DOPEG and DOPAC were reduced in 1-day-SAD rats. ME catecholamines returned toward control levels in 3- to 4-day-SAD rats. These studies show that the chronic absence of arterial baroreceptor input produces time-related, regionally specific central changes of vasopressin and regionally associated catecholamines.
本研究的目的是确定慢性动脉压力感受器缺陷是否会引起中枢血管加压素（AVP）和儿茶酚胺系统随时间的变化。在手术后1、3、4、7和14天对去窦主动脉神经支配（SAD）组和假手术（SO）组大鼠进行研究。通过对冷冻脑切片进行微量打孔获取视上核（SON）、室旁核（PVN）和弓状核（ARC）、正中隆起（ME）区域以及延髓A1区域，并检测其中的AVP、酪氨酸羟化酶（TH）活性、儿茶酚胺及其代谢产物二羟苯乙二醇（DOPEG）和2,5-二羟苯乙酸（DOPAC）。1日龄SAD大鼠SON和PVN中的AVP浓度升高，3日龄和4日龄SAD大鼠中降低，7日龄和14日龄SAD大鼠中分别等于和高于对照值。1日龄和7日龄SAD大鼠SON中的TH活性升高，ME和ARC中的TH活性降低。在SON中，1日龄SAD大鼠的DOPEG增加，而在ME中，所有儿茶酚胺、DOPEG和DOPAC均降低。3至4日龄SAD大鼠ME中的儿茶酚胺恢复至对照水平。这些研究表明，动脉压力感受器输入的长期缺失会导致血管加压素以及与之相关的儿茶酚胺出现随时间变化的、区域特异性的中枢改变。
