Application of renal microangiography to normal and diseased kidneys of cattle and mice.

Use of microangiography is now essential for the study of microcirculation in various organs. Renal microangiographic studies have been reported in rats, rabbits, dogs, human beings, and mice. However, we could not find any report on use of the technique in cattle, despite high incidence of renal disease in that species. The perfusion technique used in mice was improved over that of our previous report, and was applied to normal and diseased bovine kidneys. For the microangiographic technique, composition of the contrast medium, pressure of the injection, duration of perfusion, and washing of kidneys with heparinized saline solution before perfusion are important. In cattle, 1- to 2-mm-thick sections of the kidneys were generally necessary to observe renal vasculature: arcuate and interlobular arteries, afferent arterioles, and glomerular capillaries. In normal bovine kidneys, the angiographic and microangiographic findings were easily recognized as normal, compared with those of normal mice. In affected bovine kidneys, which histologically represented glomerulonephritis and pyelonephritis, angiography and microangiography revealed corresponding findings.