Hwang Eun-Sang, Choi Ga-Young, Kim Kwan Joong, Kim Min-Jeong, Lee Seok, Lee Jin-Won, Kim Dae-Ok, Park Ji-Ho
Department of Gerontology (Age Tech-Service Convergence Major), Graduate School of East-West Medical Science, Kyung Hee University, Yongin 17104, Republic of Korea.
Department of East-West Medicine, Graduate School of East-West Medical Science, Kyung Hee University, Yongin 17104, Republic of Korea.
Evid Based Complement Alternat Med. 2022 Jul 8;2022:9095857. doi: 10.1155/2022/9095857. eCollection 2022.
The lowering blood pressure effect of vitamin C (VC) has been evaluated in various models. As VC has a fast degradation rate in the body after consumption, a study of the frequency-dependent manner of VC is essential for the sustained antihypertension effect of VC. In this study, we investigated the frequency and dose dependency of vitamin C (VC) on blood pressure reduction in spontaneously hypertensive rats (SHRs). Wistar-Kyoto rats (WKYs) and SHRs were orally administered tap water or VC (250, 500, 1000, and 2000 mg/60 kg/day). Blood pressures were measured using the tail-cuff method, and thoracic aortas, liver, and blood were harvested from sacrificed rats after 8 weeks to measure angiotensinogen, angiotensin-converting enzyme (ACE) I, endothelial nitric oxide synthase (eNOS), and total nitric oxide (NOx) concentration. VC decreased blood pressure from the fourth week with no significant differences between doses. The twice-a-day administration of VC decreased blood pressure from the second week, and the blood pressure in these groups was close to that of the WKY group in the eighth week. Treatment with once a day VC decreased ACE I production which was further significantly reduced in twice a day groups. Angiotensinogen and eNOS production were increased upon VC treatment but were not significant among groups. The NOx content was decreased by VC treatment. These results suggest that VC lowers blood pressure in SHRs by directly targeting ACE I production in a frequency-dependent manner and may improve endothelial function depending on the frequency of administration.
维生素C（VC）的降压作用已在多种模型中得到评估。由于VC在摄入后在体内具有快速降解率，因此研究VC的频率依赖性方式对于其持续的降压作用至关重要。在本研究中，我们调查了维生素C（VC）对自发性高血压大鼠（SHRs）血压降低的频率和剂量依赖性。将Wistar-Kyoto大鼠（WKYs）和SHRs口服给予自来水或VC（250、500、1000和2000mg/60kg/天）。使用尾袖法测量血压，并在8周后从处死的大鼠中采集胸主动脉、肝脏和血液，以测量血管紧张素原、血管紧张素转换酶（ACE）I、内皮型一氧化氮合酶（eNOS）和总一氧化氮（NOx）浓度。VC从第四周开始降低血压，各剂量之间无显著差异。每天两次给予VC从第二周开始降低血压，并且这些组在第八周的血压接近WKY组。每天一次给予VC治疗可降低ACE I的产生，在每天两次给药的组中进一步显著降低。VC治疗后血管紧张素原和eNOS的产生增加，但各组之间无显著差异。VC治疗降低了NOx含量。这些结果表明，VC通过以频率依赖性方式直接靶向ACE I的产生来降低SHRs的血压，并且可能根据给药频率改善内皮功能。
