Tokunaga K, Fukushima M, Kemnitz J W, Bray G A
Endocrinology. 1986 Oct;119(4):1708-11. doi: 10.1210/endo-119-4-1708.
The effects of vagotomy on plasma glucose and insulin levels in rats with paraventricular nuclear (PVN) or ventromedial hypothalamic (VMH) lesions were measured during a constant glucose infusion. In one experiment, vagotomy was performed 50 min after the lesions, and in a second experiment, it was performed at the same time as the lesions. After the introduction of lesions in the PVN, there was a significantly greater rise in plasma glucose than in animals with either large or small VMH lesions, both of which had plasma glucose values similar to those in the sham-lesioned animals. The rise in insulin was greater in all three lesion groups than in the sham-operated animals. Although both plasma glucose and insulin had begun to decline before the vagotomy performed 50 min after lesioning, there was a further subsequent fall after vagotomy which was greater in the VMH-lesioned animals with large lesions than in rats with PVN lesions or small VMH lesions. In the sham-lesioned rats, there was no significant change in insulin or glucose after vagotomy. When the vagotomy and hypothalamic lesions were performed simultaneously, the glucose and insulin values in all groups were the same. The present experiments suggest that VMH and PVN exert different controls over pancreatic hormone secretion. The VMH lesions appear to remove an inhibitory effect on the vagus, with resultant hyperinsulinemia in the absence of hyperglycemia. The PVN-lesioned animals show a hyperglycemia which is abolished by vagotomy, suggesting that the PVN connects to vagal fibers which activate the glucagon secretory system in the alpha-cell of the pancreas.
在持续输注葡萄糖的过程中，测量了迷走神经切断术对患有室旁核（PVN）或下丘脑腹内侧核（VMH）损伤的大鼠血浆葡萄糖和胰岛素水平的影响。在一项实验中，在损伤后50分钟进行迷走神经切断术，在第二项实验中，迷走神经切断术与损伤同时进行。在PVN损伤后，血浆葡萄糖的升高明显大于VMH大损伤或小损伤的动物，这两组动物的血浆葡萄糖值与假损伤动物相似。所有三个损伤组的胰岛素升高都大于假手术动物。虽然在损伤后50分钟进行迷走神经切断术之前，血浆葡萄糖和胰岛素就已经开始下降，但迷走神经切断术后仍有进一步下降，VMH大损伤动物的下降幅度大于PVN损伤或VMH小损伤的大鼠。在假损伤大鼠中，迷走神经切断术后胰岛素或葡萄糖没有显著变化。当迷走神经切断术和下丘脑损伤同时进行时，所有组的葡萄糖和胰岛素值相同。目前的实验表明，VMH和PVN对胰腺激素分泌有不同的控制作用。VMH损伤似乎消除了对迷走神经的抑制作用，导致在无高血糖的情况下出现高胰岛素血症。PVN损伤的动物出现高血糖，迷走神经切断术可消除这种高血糖，这表明PVN与迷走神经纤维相连，这些纤维激活胰腺α细胞中的胰高血糖素分泌系统。
