SLC9A3 and hypertensive disorder: Using confocal immunofluorescent microscopic imaging, Yip et al. (1998) demonstrated that NHE3 was localized in the brush border of the microvilli in the proximal tubules of young prehypertensive SHRs, whereas in adult SHRs with established hypertension, it was found at the base of the microvilli of the proximal tubules.