Iwai M, Shimazu T
Department of Medical Biochemistry, Ehime University School of Medicine, Japan.
Life Sci. 1988;42(19):1833-40. doi: 10.1016/0024-3205(88)90021-5.
The effects of hypothalamic stimulation on experimental liver injury induced by carbon tetrachloride (CCl4) or dimethylnitrosamine (DMN) were studied in rats, by measuring plasma alanine aminotransferase (ALT) activity as an index of acute liver injury. Electrical stimulation of the ventromedial hypothalamus (VMH) in CCl4-treated rats caused a marked increase in plasma ALT activity, accompanied by a significant decrease in ALT activity in the liver, although CCl4 treatment alone had no significant effect on plasma ALT activity. A similar effect of VMH stimulation on plasma ALT activity was observed in rats treated with DMN, another hepatotoxic chemical. No such exaggerated effect of VMH stimulation on plasma ALT activity was observed after stimulation of the lateral hypothalamic area (LH). Surgical sympathetic denervation of the liver greatly suppressed the increase in plasma ALT activity after CCl4 injection and VMH stimulation. Measurement of regional blood flow indicated that VMH stimulation did not produce a significant change in blood flow to the liver. These results suggest that the VMH is involved in the progress of chemically-induced liver injury through activation of the sympathetic nerve (hepatic nerves), possibly by affecting liver metabolism more than the blood flow change to the liver.
通过测量血浆丙氨酸转氨酶（ALT）活性作为急性肝损伤指标，研究了下丘脑刺激对四氯化碳（CCl4）或二甲基亚硝胺（DMN）诱导的大鼠实验性肝损伤的影响。在CCl4处理的大鼠中，电刺激腹内侧下丘脑（VMH）导致血浆ALT活性显著升高，同时肝脏中ALT活性显著降低，尽管单独使用CCl4处理对血浆ALT活性没有显著影响。在另一种肝毒性化学物质DMN处理的大鼠中，观察到VMH刺激对血浆ALT活性有类似的影响。刺激下丘脑外侧区（LH）后，未观察到VMH刺激对血浆ALT活性有这种夸大的影响。肝脏的手术性交感神经去神经支配极大地抑制了CCl4注射和VMH刺激后血浆ALT活性的升高。局部血流量测量表明，VMH刺激并未使肝脏血流量产生显著变化。这些结果表明，VMH通过激活交感神经（肝神经）参与化学诱导的肝损伤进展，可能是通过对肝脏代谢的影响大于对肝脏血流量变化的影响。
