Stewart P L
CSIRO Australian Animal Health Laboratory, Geelong, Victoria.
Res Vet Sci. 1998 Jan-Feb;64(1):31-5. doi: 10.1016/s0034-5288(98)90111-4.
The neurological disease of livestock known as annual ryegrass toxicity, caused by ingestion of bacterial toxins called corynetoxins, has been shown to be produced experimentally by injection of tunicamycin, a related antibiotic. In this study the effects of tunicamycin inhibition on the activity of the enzyme, N-acetylglucosamine-1-phosphate transferase, in sheep liver rough microsomes were measured in vitro and in vivo. Enzyme activity was dependent on Triton X-100 and exogenous dolichyl phosphate for maximal activity, although there was measurable activity in their absence. The transferase enzyme was very sensitive to in vitro (inhibition can be detected below 10 ng ml(-1)). In vivo, sheep treated parenterally with a single dose of tunicamycin showed a time and dose-dependent decrease in enzyme activity, which was almost completely inhibited for up to 14 days after a sublethal dose of toxin. In addition, the yield of rough microsomes was lower from toxin-treated sheep than from control animals.
家畜的一种神经疾病，称为一年生黑麦草中毒，是由摄入一种名为棒杆菌毒素的细菌毒素引起的，实验表明，注射一种相关抗生素衣霉素也可引发这种疾病。在本研究中，在体外和体内测量了衣霉素抑制对绵羊肝脏粗面微粒体中N - 乙酰葡糖胺 - 1 - 磷酸转移酶活性的影响。酶活性依赖于Triton X - 100和外源性磷酸多萜醇以达到最大活性，尽管在没有它们的情况下也有可测量的活性。转移酶对体外环境非常敏感（低于10 ng ml(-1)时即可检测到抑制作用）。在体内，经肠胃外单次注射衣霉素处理的绵羊，其酶活性呈现出时间和剂量依赖性下降，在给予亚致死剂量毒素后长达14天，酶活性几乎完全被抑制。此外，毒素处理过的绵羊的粗面微粒体产量低于对照动物。
