Arteriosclerosis in the Influx and Intravisceral Arteries of the Liver, Kidney and Lung of WHHL Rabbits.

Abstract

Abstract:We performed a histopathological investigation on arteriosclerotic development in the influx and intravisceral arteries of the liver, kidney and lung of male WHHL rabbits. In the influx arteries of these organs, we observed severe atherosclerotic vascular lesions with high-grade luminal stenosis. In the intravisceral arteries of the liver and kidney, no arteriosclerotic lesions were observed. However, in the intrapulmonary arteries, we recognized severe atherosclerotic vascular changes with high-grade stenosis or total obstruction of the lumen in some middle to large sized pulmonary arteries. These observations indicate that the development of arteriosclerosis in parenchymatous organs differs, and that some organs are predisposed to arteriosclerosis formation. Key words: arteriosclerosis, organ-specificity, WHHL rabbitThe Watanabe heritable hyperlipidemic (WHHL) rabbit, which spontaneously forms atherosclerosis, has been regarded as an animal model for human atherosclerosis [1,6,10], and familial hypercholesterolemia especially [2,3,15]. There have been many reports on sclerotic lesions of the coronary artery [7,11,13,16] and aorta [4,5,8,9] until now, but there are no reports on the arterial lesions in the influx and intravisceral arteries of the parenchymatous organs, except for the heart and brain [12], in the WHHL rabbit. In the present study, we investigated histopathologically the arteriosclerotic changes in the influx and intravisceral arteries of the liver, kidney and lung, and clarified the degree and progress level of arteriosclerosis in these parenchymatous organs. Five male two-year-old WHHL rabbits weighing 3.2-3.5 kg were used in this study. The rabbits were caged in an automatically conditioned room (temperature: 22 ± 2°C; humidity: 55 ± 10%; air change: 10 times/hr; 12 hr light/12 hr dark cycle) and were fed a standard rabbit chow. Water was provided ad libitum. They were euthanatized with an over-dose of sodiumpentobarbital and the liver, kidney and lung were removed immediately including all the influx arteries. Fixation of the organs was performed by immersing in 10% buffered formalin. After paraffin embedding, 5-µm-thick sections were stained with hematoxylin-eosin (H E) or Van Gieson. In the liver, the celiac trunk bifurcation, common hepatic artery, proper hepatic artery of the porta hepatis, and interlobular artery were

Distribution of atherosclerotic lesions in various arteries of WHHLMI rabbits, an animal model of familial hypercholesterolemia

“…Kamimura et al. [15] reported intimal thickening in renal arteries at the hilum of the kidney in WHHL rabbits. In humans, most renal artery lesions are fibrous [16], but some renal arteries also have atherosclerotic lesions [7].…”