Sympathetic hyperreactivity to air-jet stress in the chromosome 1 blood pressure quantitative trait locus congenic rats
Sympathetic hyperreactivity to air-jet stress in the chromosome 1 blood pressure quantitative trait locus congenic rats
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DOI：
10.1152/ajpregu.00610.2005
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发表时间：
2006-03-01
影响因子：
2.8
通讯作者：
Takishita, S
中科院分区：
文献类型：
--
作者：
Yamazato, M;Ohya, Y;Takishita, S
将一个1号染色体血压数量性状位点（QTL）从易卒中的自发性高血压大鼠（SHRSP）向Wistar-Kyoto（WKY）大鼠进行基因渐渗。这同源株（WKYpch1.0）表现出夸张的升压反应，无论是限制和冷应激。在这项研究中，我们评估了心血管和交感神经对空气喷射压力的反应，并研究了WKYpch1.0的压力反应中脑肾素-血管紧张素系统（RAS）的作用。我们测量了平均动脉压（MAP），心率（HR），和肾交感神经活动（RSNA）的反应，空气喷射压力在WKYpch1.0，WKY，SHRSP。我们还研究了侧脑室注射血管紧张素Ⅱ 1型受体阻滞剂坎地沙坦对喷气应激的MAP和HR反应的影响。WKYpch1.0和WKY大鼠的基线MAP相当，但低于SHRSP大鼠。基线HR在菌株之间没有差异。在WKYpch1.0中，空气射流应激引起的MAP和RSNA的增加大于WKY。RSNA的增加与SHRSP一样大，而MAP的增加小于SHRSP。侧脑室注射非降压剂量的坎地沙坦抑制应激诱导的升压反应在更大程度上在WKYpch1.0比在WKY。静脉注射苯肾上腺素引起的压迫效应在WKYpch1.0和WKY之间相当。这些结果表明，1号染色体血压QTL同源大鼠具有交感神经高反应性的空气喷射压力，这会导致夸张的升压反应。这种夸张的反应至少部分是由大脑RAS介导的。
A chromosome 1 blood pressure quantitative trait locus (QTL) was introgressed from the stroke-prone spontaneously hypertensive rats (SHRSP) to Wistar-Kyoto (WKY) rats. This congenic strain (WKYpch1.0) showed an exaggerated pressor response to both restraint and cold stress. In this study, we evaluated cardiovascular and sympathetic response to an air-jet stress and also examined the role of the brain renin-angiotensin system (RAS) in the stress response of WKYpch1.0. We measured mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA) responses to air-jet stress in WKYpch1.0, WKY, and SHRSP. We also examined effects of intracerebroventricular administration of candesartan, an ANG II type 1 receptor blocker, on MAP and HR responses to air-jet stress. Baseline MAP in the WKYpch1.0 and WKY rats were comparable, while it was lower than that in SHRSP rats. Baseline HR did not differ among the strains. In WKYpch1.0, air-jet stress caused greater increase in MAP and RSNA than in WKY. The increase in RSNA was as large as that in SHRSP, whereas the increase in MAP was smaller than in SHRSP. Intracerebroventricular injection of a nondepressor dose of candesartan inhibited the stress-induced pressor response to a greater extent in WKYpch1.0 than in WKY. Intravenous injection of phenylephrine caused a presser effect comparable between WKYpch1.0 and WKY. These results suggest that the chromosome 1 blood pressure QTL congenic rat has a sympathetic hyperreactivity to an air-jet stress, which causes exaggerated pressor responses. The exaggerated response is at least partly mediated by the brain RAS.