Soares Angélica, Schoffen João Paulo Ferreira, De Gouveia Elsa Maria, Natali Maria Raquel Marçal
Enteric Neurons Laboratory, Department of Morphophysiological Sciences, State University of Maringá, Av. Colombo 5790, Maringá-Paraná, PR, 87020-900, Brazil.
J Gastroenterol. 2006 Jul;41(7):674-80. doi: 10.1007/s00535-006-1839-5.
The neonatal administration of a 4 mg/g dose of monosodium glutamate (MSG) to rodents leads to neuronal death in the hypothalamus arcuate nucleus, which leads in turn to obesity in the adult animal. However, few studies have investigated the effects on the enteric nervous system. This study evaluated the effects of the neonatal administration of MSG on the frequency and morphometry of the myenteric as well as the ileum wall morphometry of adult Wistar male rats.
Whole-mount preparations of ileum samples were stained by the Giemsa or NADH-diaphorase histochemical methods. For histological processing, hematoxylin and eosin staining was used.
The treatment with MSG led to obesity, as shown by the higher values for Lee's index and the weights of periepididimal and retroperitoneal adipose tissues. The Giemsa staining revealed a significantly larger neuronal density in the MSG group, which is explained by smaller physical growth and a reduction in the weight of the small intestine. The mean neuronal profile did not change between groups. The NADH-diaphorase-positive neuronal subpopulation kept its neuronal density but its average cellular profile was reduced in the MSG group. A morphometric analysis of the intestinal wall, muscular layer, villi, and intestinal crypts showed that their characteristics did not change.
The treatment with MSG did not cause alteration of the total myenteric population of the ileum, but it influenced the NADH-diaphorase-positive subpopulation. From the maintenance of the morphometric parameters of the ileum intestinal wall, we inferred that intestinal function was preserved in obese animals.
给啮齿动物新生期注射4mg/g剂量的味精（MSG）会导致下丘脑弓状核的神经元死亡，进而导致成年动物肥胖。然而，很少有研究调查其对肠神经系统的影响。本研究评估了新生期注射MSG对成年雄性Wistar大鼠肌间神经丛的频率和形态计量学以及回肠壁形态计量学的影响。
回肠样本的整装标本用吉姆萨或NADH-黄递酶组织化学方法染色。对于组织学处理，使用苏木精和伊红染色。
MSG处理导致肥胖，Lee指数以及附睾周围和腹膜后脂肪组织重量的较高值表明了这一点。吉姆萨染色显示MSG组的神经元密度显著更大，这可以用身体生长较小和小肠重量减轻来解释。各组之间平均神经元轮廓没有变化。MSG组中NADH-黄递酶阳性神经元亚群的神经元密度保持不变，但其平均细胞轮廓减小。对肠壁、肌层、绒毛和肠隐窝的形态计量学分析表明，它们的特征没有变化。
MSG处理并未引起回肠肌间神经丛总数的改变，但影响了NADH-黄递酶阳性亚群。从回肠肠壁形态计量学参数的维持情况来看，我们推断肥胖动物的肠道功能得以保留。
