Identification of microvascular network patterning alterations in young spontaneously hypertensive rats

Abstract

Microvascular rarefaction, defined by a loss of arterioles and/or capillaries, is a common characteristic of hypertension. Recent work in our laboratory suggests that microvascular rarefaction in adult spontaneous hypertension rats is more complex and is also associated with network patterning alterations. The objective of this study was to compare the microvascular architectures in young hypertensive versus normotensive rats. Mesenteric tissues from age‐matched (7‐8 weeks) male spontaneously hypertensive (SHR; n=13), Wistar‐Kyoto (WKY; n=7), and Wistar (n=8) rats were harvested and immunolabeled with PECAM, an endothelial cell marker. SHR microvascular networks displayed reduced branching, increased arteriole/venous shunts and increased arteriole/venous anastomoses proximal to the capillary level. These observations indicate that network patterning alterations in addition to fewer microvessels are present prior to the establishment of hypertension.