Morphoquantitative study of the submucous plexus (of Meissner) of the jejunum-ileum of young and old guinea pigs / Estudo morfoquantitativo do plexo submucoso (de Meissner) do jejuno-íleo de cobaias jovens e velhas

OBJECTIVE: To study the aging of submucous plexus of the small intestine (jejunum-ileum) of the guinea pigs from the quantitative, structural and ultrastructural perspective. METHOD: Chemical preparations of membrane of the jejunum-ileum of old and young animals with the use of light and electronic microscope. RESULTS: The ganglia of young animals presented between 1 and 56 neurons and the old animals presented from 1 to 30 neurons. The mean density of the ganglia by cm² in the young jejunum-ileum was of 551±36.89 and in the old one 413±11.86. The density of the neurons was 5011±291.11 neurons/cm² average in young animals and 2918±120.70 neurons/cm² in the old ones. The size of the neurons varied in both age groups. The collagen fibers in the ganglia of old animals they were condensed. Degenerated mitochondrias in the interior of the cell were frequent in the old animals. CONCLUSION: In submucous plexus of the jejunum-ileum there is a loss of 38 percent of the neurons with aging.

OBJETIVO: Estudar o envelhecimento do plexo submucoso do intestino delgado (jejuno-íleo) das cobaias do ponto de vista quantitativo, estrutural e ultra-estrutural. MÉTODO: Preparados de membrana do jejuno-íleo de animais jovens e velhos com a utilização de microscopia de luz e eletrônica. RESULTADOS: Os gânglios de animais jovens apresentaram entre 1 e 56 neurônios e os animais velhos apresentaram de 1 a 30 neurônios. A densidade média dos gânglios por cm² no jejuno-íleo jovem foi de 551±36,89 e no velho foi de 413±11,86. A densidade dos neurônios foi de 5011±291,11 neurônios/cm² em média nos animais jovens e 2918±120,70 neurônios/cm² nos velhos. O tamanho dos neurônios variou em ambos os grupos etários. As fibras colágenas nos gânglios de animais velhos estavam mais condensadas. Mitocôndrias degeneradas no interior da célula foram freqüentes nos animais velhos. CONCLUSÃO: No plexo submucoso do jejuno-íleo há uma perda de 38 por cento dos neurônios com o envelhecimento.

Distribution and properties of P2 receptors in enteric nervous system / 第二军医大学学报

Enteric nervous system consists of myenteric and submucous plexuses. Myenteric plexus mainly innervates the enteric motion; submucous plexus modulates the gastrointestinal secretion and local blood flow. P2 (ATP) receptors exist in both of the above plexuses and play an important role under physiological and pathophysiological conditions. This article reviews the distribution, function and pharmacological characteristics of different P2 receptors, in an effort to provide new evidence for studying the role of P2 receptors in the diagnosis and therapy of enteric diseases.

The Morphometric and Ultrastructural Study of Enteric Nervous System in Adult and Aged Rat Small Intestine / 대한해부학회지

This study was performed to investigate the morphometric and ultrastructural change in the adult and aged rat small intestine. The myenteric and submucous plexuses were stained by NADH-TR in the ileum of adult Sprague-Dawley rats (3 mo., 300~350 gm) and aged rats (24 mo., 500~550 gm). The neurons of myenteric and sumucous plexuses were divided into 3 groups depending on their cell body morphology. Type 1 cells were polygonal or round with abundant cytoplasm. Type 2 cells were spindle shaped and type 3 cells were small and round with scanty cytoplasm. The nerve cell numbers and sizes were measured using an image analyzer (VIDAS, Carl Zeiss, Co., Ltd.). Ultrastructural changes were observed by JEM-1200 EXII (JEOL Co., Ltd.) electron microscope. The result obtained are as followed: 1. In adult rats, majority of neuron population were type 3 and neuron density (total numbers/1 mm2) was more higher in submucous plexus than in the myenteric plexus. 2. Statistically significant loss of type 1 and type 2 neurons were in myenteric and submucous plexus of aged rat small intestine. 3. All types of neuron sizes were increased in aged myenteric and submucous plexuses. 4. Lipofusin granules were prominent in the cytoplasm of aged rat. Cell organelles were not shown degenerative change. These results suggest that type 1 and type 2 nerve cells which is originated from autonomic nerves were lost in aged rat small intestine. Ultrastructurally lipofusin granules were prominent in the cytoplasm of aged rat and the cell organelles were not degenerated.