Iglésias-Barreira V, Ahn M T, Reusens B, Dahri S, Hoet J J, Remacle C
Laboratoire de Biologie Cellulaire, Université Catholique de Louvain, Louvain-La Neuve, Belgium.
Endocrinology. 1996 Sep;137(9):3797-801. doi: 10.1210/endo.137.9.8756549.
The pancreatic islet blood flow and insulin secretion of adult rats submitted to an isocaloric low protein diet (8% vs. 20%) during pre- and postnatal life were investigated by the nonradioactive microsphere technique. In the basal state, female rats chronically exposed to a low protein diet (LP) displayed a specific marked decrease in islet blood flow (10 +/- 2 vs. 29 +/- 5 microliters/min.g pancreas; P < 0.01) and overall pancreatic blood flow (P < 0.01). The plasma insulin level, however, was not affected. During a glucose challenge, the control animals enhanced their islet blood flow 2.3-fold, whereas the LP group reached control values with a 6-fold increase. Plasma insulin levels rose similarly in the control and LP animals. A third group of animals designated the recuperation group, exposed to a low protein diet only in utero, displayed islet blood flow comparable to control values, but increased basal plasma insulin (2.0 +/- 0.3 vs. 1.2 +/- 0.1 ng/ml; P < 0.05). These data are consistent with the possibility of dissociation of islet blood flow and insulin release under basal conditions, which may not be the case after a glucose challenge. Furthermore, the low blood flow values in the LP group may reflect an adaptive physiological response, an impaired pancreatic vasculogenesis, or a dysfunction of endothelial cells.
采用非放射性微球技术，研究了在出生前后接受等热量低蛋白饮食（8% 对 20%）的成年大鼠的胰岛血流和胰岛素分泌情况。在基础状态下，长期暴露于低蛋白饮食（LP）的雌性大鼠胰岛血流（10±2 对 29±5 微升/分钟·克胰腺；P<0.01）和胰腺整体血流显著降低（P<0.01）。然而，血浆胰岛素水平未受影响。在葡萄糖激发试验中，对照动物的胰岛血流增加了 2.3 倍，而 LP 组增加了 6 倍才达到对照值。对照动物和 LP 动物的血浆胰岛素水平升高幅度相似。第三组动物为恢复组，仅在子宫内暴露于低蛋白饮食，其胰岛血流与对照值相当，但基础血浆胰岛素水平升高（2.0±0.3 对 1.2±0.1 纳克/毫升；P<0.05）。这些数据表明，在基础条件下胰岛血流和胰岛素释放可能解离，但在葡萄糖激发试验后可能并非如此。此外，LP 组的低血流值可能反映了一种适应性生理反应、胰腺血管生成受损或内皮细胞功能障碍。
