Methylglyoxal Accumulation in Arterial Walls Causes Vascular Contractile Dysfunction in Spontaneously Hypertensive Rats

• Main Authors: Masashi Mukohda (Author), Muneyoshi Okada (Author), Yukio Hara (Author), Hideyuki Yamawaki (Author)
• Format: Book
• Published: Elsevier, 2012-01-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Methylglyoxal (MGO) is a metabolite of glucose and perhaps mediates diabetes-related macrovascular complications including hypertension. In the present study, we examined if MGO accumulation affects vascular reactivity of isolated mesenteric artery from spontaneously hypertensive rats (SHR). Five-week-old SHR were treated with an MGO scavenger, aminoguanidine (AG), for 5 weeks. AG partially normalized increased blood pressure in SHR. In mesenteric artery from SHR treated with AG, increased accumulation of MGO-derived advanced glycation end-products was reversed. In mesenteric artery from SHR, AG normalized impaired acetylcholine (ACh)-induced relaxation and increased angiotensin (Ang) II-induced contraction. Reactive oxygen species (ROS) production increased in SHR mesenteric artery, and acute treatment with a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) inhibitor augmented ACh-induced relaxation. Protein expression of NOX1 and Ang II type 2 receptor (AT2R) increased in SHR mesenteric artery, which was normalized by AG. Acute treatment with an AT2R blocker but not a NOX inhibitor normalized the increased Ang II-induced contraction in SHR mesenteric artery. The present results demonstrate that MGO accumulation in mesenteric artery may mediate development of hypertension in SHR at least in part via increased ROS-mediated impairment of endothelium-dependent relaxation and AT2R-mediated increased Ang II contraction. Keywords:: glucose metabolite, smooth muscle, endothelium, vascular reactivity, reactive oxygen species

Item Description

1347-8613
10.1254/jphs.12088FP