Abstract-Current mlcroscoplc methods to view renal mlcrovasculature reveal only a very hmlted portion of the total renal volume Identlficatlon of connectlvlty for postglomerular vessels m the cortex and the medulla durmg functional states related to changes m sodium excretion will help better to understand the couplmg of renal vasculature to tubular function The purpose of this study was to investigate the posslblhty of vlsuahzmg the contmmty of pre-and postglomerular vasculature using three-dlmennonal micro-computed tomography ( micro-CT) Kidneys from normal rats were perfusion fixed m situ at physlologlcal pressure, filled with latex mlcrofil contammg lead chromate, and embedded m plastic The micro-CT scans of the intact kidneys were carned out on a rotating stage lllummated either by a synchrotron x-ray source or a conventional x-ray spectroscopy tube Images were reconstructed by a filtered backproJection algorithm and volume-rendering techniques were utilized to display the vasculature The reconstructed images clearly showed the large dlstrlbutlon vessels and the venous dramage of the kidneys, while pre-and postglomerular vessels and their vascular connections throughout the kidney were displayed m great detail Efferent artenoles showed the charactenstlcs of then perltubular capillary beds m the cortical and medullary regions The vascular volume of the cortex was 27%, the outer stripe of the outer medulla 18%, the mner stripe of the outer medulla 30%, and the mner medulla 18% In conclusion, micro-CT 1s a promlsmg method to evaluate renal vascular architecture relative to phynologcal and pathological alterations (Hypertension.

The results indicate that after CBDL, there is a selective decrease in cortical vascular filling, which may contribute to the salt and water retention that accompanies cirrhosis.