脂肪肝•脂肪性肝硬変における肝内血管の変化に関する実験的研究

1. 脂肪肝における変化

抄録

The mechanism of portal hypertension in fatty liver and correlation between vascular changes and histogenesis of fatty liver and cirrhosis were studied. The rats were sacrificed after 1, 3, 5, 10, 15 and 20 weeks following the administration of the choline-deficient diet prescribed by György et al. Intra-hepatic vascular changes were observed by means of a preparation of liver infused with colored plastik or gelatin. Portal pressure was estimated from intra-splenic pressure.
The livers of choline-deficient rats revealed the following histological changes: hepatic cells were filled with small fat droplets in one week and with large fat droplets in three weeks. During five weeks the fatty cysts were formed in the cells. In the severest cases, hepatic fibrosis and cirrhosis occurred after ten and twenty weeks respectively. Portal pressure was distinctly increased in three weeks, although a moderate decrease after five weeks was noted. Then it became gradually increased up to twenty weeks. Pronounced narrowing of the sinusoids were noted in three weeks and continued up to five weeks, although portal pressure decreased after five weeks. Later the narrowing of sinusoids became more marked. After 15 weeks, when fibrosis occurred, anastomo ses between the terminal branches of hepatic vein with occasional increase of surrounding connective tissue fiber were seen. At this stage the increase of arterio-venous anastomoses or tortuous hepatic artery and portal vein was not observed.
From above findings of fatty liver in the rats, it is considered that portal hypertension was mainly attributed to compression of sinusoids by marked increase in hepatic cell volume with fat accumulation. Formation of fatty cysts probably relieved the compression of sinusoids. At the later stage of fatty liver there was no change of hepatic arterial and portal beds, although anastomoses between the terminal branches of hepatic vein were formed.