Hidiroglou M, Karpinski K
Animal Research Centre, Agriculture Canada, Ottawa, Ontario.
Br J Nutr. 1991 May;65(3):465-73. doi: 10.1079/bjn19910105.
Three experiments were conducted to estimate the effects of single intramuscular (IM) administrations of vitamin E on blood plasma and tissue concentrations of alpha-tocopherol in sheep. In Expt 1, plasma kinetics of alpha-tocopherol in sheep (n 30) were investigated following IM administration of three doses (ten sheep/dose) of DL-alpha-tocopheryl acetate, (20, 40 and 60 mg/kg live weight). Plasma profiles of alpha-tocopherol consisted of a lag phase followed by an apparent first-order absorption and elimination phase. The rate of absorption and elimination, as well as the lag phase, were independent of the dose, but the extent of absorption was directly proportional to dose. In Expt 2 (eighteen experimental and five control sheep), the animals were injected as in Expt 1 and were killed at 0, 80 and 176 h. Increases in alpha-tocopherol levels in organs were much higher than in plasma. Some tissues such as liver, spleen, lung and adrenal appeared to exhibit rapid absorption and elimination phases. The amount absorbed was proportional to the dose administered. Other organs such as heart, kidney and pancreas had a slow elimination rate. In Expt 3, D-alpha-tocopherol was injected IM into ten sheep at either 604 mg or 1208 mg. The mean hepatic alpha-tocopherol concentrations in both groups rose rapidly and after 4 weeks of dosing its concentrations were higher than the predosing levels. The increase in hepatic tocopherol concentrations were higher following 1208 mg dosing than 604 mg D-alpha-tocopherol. No simple relationship existed between plasma and hepatic alpha-tocopherol concentrations. This suggests a difference in body mechanisms controlling vitamin E in blood and liver.
进行了三项试验以评估单次肌肉注射维生素E对绵羊血浆和组织中α-生育酚浓度的影响。在试验1中，对30只绵羊（每组10只）肌肉注射三种剂量（20、40和60mg/kg体重）的DL-α-生育酚醋酸酯，研究α-生育酚的血浆动力学。α-生育酚的血浆曲线包括一个滞后阶段，随后是一个明显的一级吸收和消除阶段。吸收和消除速率以及滞后阶段与剂量无关，但吸收程度与剂量成正比。在试验2（18只试验羊和5只对照羊）中，动物的注射方式与试验1相同，并在0、80和176小时处死。器官中α-生育酚水平的增加远高于血浆中的增加。一些组织如肝脏、脾脏、肺和肾上腺似乎表现出快速的吸收和消除阶段。吸收量与给药剂量成正比。其他器官如心脏、肾脏和胰腺的消除速率较慢。在试验3中，对10只绵羊分别肌肉注射604mg或1208mg的D-α-生育酚。两组肝脏中α-生育酚的平均浓度迅速上升，给药4周后其浓度高于给药前水平。给予1208mg剂量后肝脏生育酚浓度的增加高于给予604mg D-α-生育酚。血浆和肝脏中α-生育酚浓度之间不存在简单的关系。这表明机体控制血液和肝脏中维生素E的机制存在差异。
