Pakarinen M P, Miettinen T A, Kuusanmäki P, Halttunen J
Second Department of Surgery, Helsinki University Central Hospital, Finland.
Surgery. 1996 Nov;120(5):822-30. doi: 10.1016/s0039-6060(96)80090-0.
Cholesterol, long-chain fatty acids, and fat-soluble vitamins are absorbed mainly in the upper small intestine and bile acids in the terminal ileum. This study determined the consequences of ileal autotransplantation on cholesterol metabolism, plasma fatty acids, and vitamin A absorption.
Plasma lipids, cholesterol precursors, plant sterols, cholestanol, fatty acids, vitamin A absorption, and animal growth were studied for 3 months after transection (n = 5), jejunal (50%) resection (n = 7), jejunal (50%) resection combined with orthotopic ileal autotransplantation (n = 7), and enterectomy (n = 7).
Cholesterol precursor to cholesterol proportions in plasma (reflect cholesterol synthesis) remained unchanged after transection and jejunal resection. The plasma plant sterol proportions (reflect cholesterol absorption) and retinol absorption increased after transection and less significantly after jejunal resection, whereas plasma fatty acid compositions were virtually unchanged. Transplantation of ileum and enterectomy amended up to sixfold the precursor proportions (p < 0.05 versus transection or jejunal resection) and impaired body weight gain. The plant sterol proportions, vitamin A absorption, and plasma cholesterol levels, respectively, were significantly (p < 0.05) decreased after transplantation when compared with those of the transected control group but remained markedly higher than those in the enterectomized group. Linoleic acid was significantly (p < 0.05 versus transection) decreased, whereas monoenoic fatty acids and eicosatrienoic acid were increased (p < 0.05 versus jejunal resection) in plasma lipids.
These results indicate that autotransplantation of ileum in pigs that have undergone jejunectomy impairs sterol, essential fatty acid, and vitamin A absorption so that plasma cholesterol levels decrease despite markedly increased cholesterol synthesis and that these changes clearly exceed those found after jejunal resection alone.
胆固醇、长链脂肪酸和脂溶性维生素主要在小肠上段吸收，而胆汁酸在回肠末端吸收。本研究确定了回肠自体移植对胆固醇代谢、血浆脂肪酸和维生素A吸收的影响。
在横断术（n = 5）、空肠（50%）切除术（n = 7）、空肠（50%）切除术联合原位回肠自体移植术（n = 7）和肠切除术（n = 7）后3个月，对血浆脂质、胆固醇前体、植物甾醇、胆甾烷醇、脂肪酸、维生素A吸收和动物生长情况进行研究。
横断术和空肠切除术后，血浆中胆固醇前体与胆固醇的比例（反映胆固醇合成）保持不变。横断术后血浆植物甾醇比例（反映胆固醇吸收）和视黄醇吸收增加，空肠切除术后增加幅度较小，而血浆脂肪酸组成基本不变。回肠移植和肠切除术使前体比例增加了高达六倍（与横断术或空肠切除术相比，p < 0.05），并损害了体重增加。与横断对照组相比，移植后植物甾醇比例、维生素A吸收和血浆胆固醇水平分别显著降低（p < 0.05），但仍明显高于肠切除组。血浆脂质中，亚油酸显著降低（与横断术相比，p < 0.05），而单不饱和脂肪酸和二十碳三烯酸增加（与空肠切除术相比，p < 0.05）。
这些结果表明，空肠切除术后猪的回肠自体移植会损害甾醇、必需脂肪酸和维生素A的吸收，从而使血浆胆固醇水平降低，尽管胆固醇合成显著增加，且这些变化明显超过单纯空肠切除术后的变化。
