Evaluation of Renal Microvasculature Using Micro-computed Tomography in Rat

Abstract

Purpose: Rodent models that mimic human renal diseases are being increasingly recognized as powerful tools in the development of new drugs and for evaluating the efficacy of novel therapeutics in a preclinical setting. However, there are few reports on microvasculature imaging of the urinary system in small animals. An experimental study was performed to evaluate the microvasculature in a rat kidney using microcomputed tomography (CT) with three-dimensional images. Materials and Methods: Five Sprague-Dawley male rats (age: 10-12 weeks, weight: 200-250g) underwent a laparotomy under anesthesia with an intramuscular injection of 0.5cc xylazine hydrochloride and ketamine mixed solution (1:10). After ligation of the abdominal aorta and inferior vena cava immediately above the renal artery, a 24 gazed catheter was inserted into the abdominal aorta. A physiological solution and heparin (500U) were infused through the catheter to flush the blood from the renal vasculature. The kidney was enhanced using self-made contrast material. The excised kidney was frozen for the micro-CT scan. Results: The mean longitudinal diameter and weight of the 10 resected kidneys was 1.95±0.15cm and 2.0±0.28g, respectively. The images were represented by three-dimensional arrays of cubic voxels with opacities in the blood vessels. In the section taken from the arrays, four regions of the kidney could be identified easily by their characteristic vascular features. Conclusions: Micro-CT is a promising method for evaluating the renal microvascular architecture in a rat kidney. It can for the foundation of an experimental study aimed at providing quantitative information on the urinary system in a rodent model. (Korean J Urol 2008;49:669-674) 󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏