Resistance vessel structure in hypertension: growth or remodeling?

Essential hypertension is associated with alterations in the structure of the resistance vessels such that the ratio of the media thickness to the lumen diameter (media: lumen ratio) is increased. This altered structure need not, however, be associated with growth but could be due to a rearrangement of a normal amount of material around a smaller lumen, a process called "remodeling." This article reviews evidence for the relative contributions of growth and remodeling regarding subcutaneous resistance arteries taken from patients with essential hypertension and mesenteric resistance arteries taken from transgenic hypertensive rats. The results suggest that in both cases, the increased media:lumen ratio is due more to remodeling than to growth. These data therefore raise some doubts as to whether growth factors play an important role in the etiology of essential hypertension.