Age-related changes in the myenteric plexus of the human jejunum

Background: Myenteric ganglia are an important regulator of peristaltic activity of the digestive tract. Getting to know its normal morphological changes during aging are of great importance for the interpretation of intestinal motility disorders. The aim of our histomorphometric study was to reveal detailed characteristics of myenteric plexus, cell number, orientation, properties of as well as age-related changes in the human jejunum. Materials and methods: We examined the myenteric ganglia in the proximal jejunum specimens obtained from 30 human cadavers aged from 20 to 84 years. Tissue samples were classified into three age groups: 20-44, 45-64 and 65-84 years. After standard histological preparation, specimens were stained with haematoxylin and eosin method, Cresyl-Violet and silver nitrate (AgNO3) by the method of Masson Fontana. In addition to standard staining methods we use and enzyme histochemical method for acetylcholinesterase. Morphometric analysis of all the specimens was performed, using a multipurpose test system M42. The data were subjected to the Tukey post hoc HSD significance test using one-way ANOVA. There is a significant decrease (p < 0.001) in the number of neurons in persons aged between 65 and 84 years. Results: It was found that the reduction in number of neurons is 25.93% in oldest compared to the youngest. It was also noted a significant increase (p < 0.05) of the surface profile of ganglion neurons. Conclusions: This increase in the size of neurons can be explained as compensation for the loss in the number of neurons in order to maintain the normal function of innervations of the jejunum.