Morphometric and quantitative study of the myenteric neurons of the stomach of malnourished aging rats

Abstract

In this work, two groups of Wistar rats were fed ad libitum, one with standard chow (22% protein) and the other with hypoproteic chow (8% protein), from the 210th to the 345th day of life. Compared to the animals fed with standard chow, the animals fed with hypoproteic chow exhibited hypophagia (ingestion about 30% lower), mean weight gain 4.46% lower, greater amount of retroperitoneal and peri-epididymal fat (19% on average), lower Lee index, decrease of total plasma proteins and plasma globulins and maintenance of plasma albumin. The quantitative and morphometric analysis of the NADH-diaphorase positive myenteric neurons yielded a larger number of small neurons and a smaller number of medium neurons in the animals subjected to the hypoproteic chow, demonstrating that the neuronal growth was affected by the diet. In the animals fed with hypoproteic chow, a 20% decrease in the NADH-diaphorase positive neurons of the forestomach and a 10% decrease in those of the glandular stomach were observed.

Oral dependent-dose toxoplasmic infection model induced by oocysts in rats: Myenteric plexus and jejunal wall changes

“…Neuronal visualization using NADH-d histochemistry is based on the formation of a formazan precipitate that occurs as NBT is reduced at the expense of NADH oxidation in a reaction catalyzed by complex I of the mitochondrial electron transport chain (Berridge et al, 2005). When the NADH-d technique is used while maintaining the same incubation times for all whole mounts, as in the present study, the degree of metabolic activity of myenteric neurons from different experimental treatments can be compared (de Sousa and de Miranda Neto, 2009). Thus, the reduction in the density of NADH-dp neurons indicates that the parasitic infection negatively affected the neurons, reducing their metabolic activity and possibly compromising mitochondrial function via indirect mechanisms, such as inflammation, because T. gondii induces Bcl-2 overexpression in the parasitized cells.…”

Chronic ingestion of deoxynivalenol‐contaminated diet dose‐dependently decreases the area of myenteric neurons and gliocytes of rats

“…The study of neurons subpopulation was performed by histochemistry for NADH‐diaphorase activity (NADH‐diaphorase positive) Samples of jejunum were filled with Krebs solution (pH 7.3) and washed twice in this solution for 10 minutes each wash. Later, the samples were immersed for five minutes in Krebs solution containing 0.3% Triton X‐100 (Sigma‐Aldrich) and washed twice in Krebs solution for 10 minutes each wash. Next, the samples remained immersed for 45 minutes in an incubation bath containing 25 mL of 0.5% nitro blue tetrazolium (NBT) stock solution (Sigma); 25 mL phosphate buffer 0.1 mol/L pH 7.3; 50 mL distilled water; and 50 mg of β‐NADH (Sigma). The reaction was interrupted by fixation of the samples in 10% formalin solution.…”

“…The study of neurons subpopulation was performed by histochemistry for NADH-diaphorase activity (NADH-diaphorase positive) 16 The samples were kept in this fixative for at least 24 hours before being processed to obtain whole-mounts and mounted as permanent slides.…”

Aging and gastrointestinal neuromuscular function: insights from within and outside the gut

“…The composition of the diet is likely important. For example, a recent study examined the effect of a hypoproteic (8% protein vs 22% protein in controls) diet on myenteric neurons in the Wistar rat 82 . Morphometric analysis of the nitrergic (NADH‐diaphorase) positive myenteric neurons demonstrated a larger number of small neurons and a smaller number of medium neurons in the animals receiving the hypoproteic chow, suggesting that the neuronal growth was affected by the diet.…”