Sarzani R, Arnaldi G, Takasaki I, Brecher P, Chobanian A V
Whitaker Cardiovascular Institute, Boston University School of Medicine, MA 02118.
Hypertension. 1991 Nov;18(5 Suppl):III93-9. doi: 10.1161/01.hyp.18.5_suppl.iii93.
Previous investigations have demonstrated certain similarities in the cellular changes occurring in the arterial wall in response to hypertension and aging. We undertook the current studies to examine the expression of platelet-derived growth factor (PDGF) receptors and ligands and transforming growth factor-beta 1 (TGF-beta 1) in aorta and heart of spontaneously hypertensive rats (SHRs), Wistar-Kyoto (WKY) controls, and Wistar rats studied at ages ranging from 5 to 40 weeks. A progressive increase with age in aortic steady-state messenger RNA (mRNA) levels of the receptor for the B chain of PDGF (PDGF-r beta) was present in all three strains but was greatest in the SHR. The aortic expression of PDGF A or B ligands as well as of the PDGF-r alpha-receptor was not significantly influenced by age or blood pressure. In contrast, in the heart of the SHR and WKY rat, there was an age-related decrease in expression of both PDGF receptors and of the PDGF B chain. Hypertension and aging were associated with increases in steady-state mRNA for TGF-beta 1 in aorta, but in the heart, reductions again were observed. These studies indicate that both hypertension and aging increase the in vivo expression of PDGF-r beta and TGF-beta 1 in aortic tissue. Such changes might be functionally significant and provide autocrine or paracrine mechanisms for regulation of cellular growth in the arterial wall in response to these conditions. The findings also provide further support for the concept that hypertension accelerates the arterial changes associated with aging.
先前的研究已证明，动脉壁因高血压和衰老而发生的细胞变化存在某些相似之处。我们开展了当前的研究，以检测自发性高血压大鼠（SHR）、Wistar-Kyoto（WKY）对照大鼠以及年龄在5至40周之间的Wistar大鼠的主动脉和心脏中血小板衍生生长因子（PDGF）受体和配体以及转化生长因子-β1（TGF-β1）的表达情况。在所有三个品系中，随着年龄的增长，主动脉中PDGF B链受体（PDGF-rβ）的稳态信使核糖核酸（mRNA）水平均呈进行性增加，但在SHR中增加最为显著。PDGF A或B配体以及PDGF-rα受体的主动脉表达不受年龄或血压的显著影响。相比之下，在SHR和WKY大鼠的心脏中，PDGF受体和PDGF B链的表达均随年龄增长而降低。高血压和衰老与主动脉中TGF-β1的稳态mRNA增加有关，但在心脏中，再次观察到降低。这些研究表明，高血压和衰老均会增加主动脉组织中PDGF-rβ和TGF-β1的体内表达。此类变化可能具有功能意义，并为动脉壁细胞生长在这些情况下的调节提供自分泌或旁分泌机制。这些发现还为高血压加速与衰老相关的动脉变化这一概念提供了进一步的支持。
