Ayala A, Tu Y, Flye M W, Chaudry I H
Department of Surgery, Michigan State University, East Lansing, USA.
Arch Surg. 1996 Nov;131(11):1209-14; discussion 1215. doi: 10.1001/archsurg.1996.01430230091016.
To determine whether redirecting intestinal blood flow away from the liver via a portacaval shunt would protect distal immune responses in the spleen after hemorrhage.
Type C3H/HeN male mice in which a portacaval shunt had been established 2 to 3 weeks before the experiment were bled, their blood pressure was maintained at 35 mm Hg for 1 hour, and then they were resuscitated. Twenty-four hours later, the mice were killed, and mixed and adherent splenocyte cultures were established. The proliferative capacity of splenocytes, the release of interleukin-2 and interleukin-4, and the ability of splenic macrophages to present the antigen, conalbumin, were then determined as indexes of immunocompetence.
The results indicate that splenocyte proliferation and splenocyte interleukin-2, but not interleukin-4, release were decreased and that splenic macrophage antigen presentation declined after hemorrhage. However, animals in which a portacaval shunt had been established before hemorrhage showed no such changes in their splenocyte or splenic macrophage functions. Thus, the decline of splenic immune responses after hemorrhage seems to be due to mediators released from the gut. Such mediators, in turn, stimulate Kupffer cells to secrete additional agents that produce immunosuppressive exocrine effects on splenic immune functions.
确定通过门腔分流术使肠道血流改道远离肝脏是否能在出血后保护脾脏的远端免疫反应。
选用在实验前2至3周已建立门腔分流术的C3H/HeN雄性小鼠，对其进行放血，将血压维持在35毫米汞柱1小时，然后进行复苏。24小时后，处死小鼠，建立混合脾细胞和贴壁脾细胞培养物。然后测定脾细胞的增殖能力、白细胞介素-2和白细胞介素-4的释放以及脾巨噬细胞呈递抗原（伴清蛋白）的能力，以此作为免疫能力的指标。
结果表明，出血后脾细胞增殖以及脾细胞白细胞介素-2（而非白细胞介素-4）的释放减少，且脾巨噬细胞的抗原呈递能力下降。然而，出血前已建立门腔分流术的动物，其脾细胞或脾巨噬细胞功能未出现此类变化。因此，出血后脾免疫反应的下降似乎是由于肠道释放的介质所致。反过来，这些介质刺激枯否细胞分泌其他对脾免疫功能产生免疫抑制外分泌作用的物质。
