Immunocytochemical Detection of Neuronal Nitric Oxide Synthase (nNOS)-IR in Embryonic Rat Stomach Between Days 13 and 21 of Gestation

Abstract

In this study, the localization and appearance of neuronal nitric oxide synthase-immunoreactive (nNOS-IR) nerve cells and their relationships with the developing gastric layers were studied by immunocytochemistry techniques and light microscopy in embryonic rat stomach. The stomachs of Wistar rat embryos aged 13-21 days were used. The first nerve cells containing nNOS-IR were seen on embryonic Day 14. The occurrence of mesenchymal cell condensation near nNOS-IR neuroblasts on embryonic Day 15 may reflect an active nerve element-specific mesenchymal cell induction causing the morphogenesis of muscle cells. Similarly, the appearance of glandular structures after nNOS-IR neuroblasts, on embryonic Day 18, suggests that the epithelial differentiation may depend on inputs coming from nNOS-IR neuroblasts, as well as other factors. Observation of nNOS-IR nerve fibers on embryonic Day 21 demonstrates that at this stage they contribute to nonadrenergic noncholinergic relaxation. In conclusion, depending on this study's results, it can be said that cells and tissues might be affected by NO secreted by nNOS-IR nerve cells during the development and differentiation of embryonic rat stomach.

Neurochemical coding of enteric neurons in adult and embryonic zebrafish (Danio rerio)

“…Despite the presence of enteric nitrergic neurons at this early stage, an NO‐mediated inhibitory tonus has been reported to be present only just before or at the onset of exogenous feeding (Holmberg et al, 2006). This is similar to what has been suggested for other vertebrate species (Timmermans et al, 1994; Van Ginneken et al, 1998, 2001; Bagyanszki et al, 2000; Belai and Burnstock, 2000; Bayram et al, 2002; Pederzoli et al, 2007). Furthermore, an additional role for nNOS has been proposed in the development and differentiation of the embryonic zebrafish gut (Holmqvist et al, 2004).…”

Immunocytochemical Detection of Synaptophysin in Enteric Neurones during Prenatal Development in the Rat Stomach

“…One of the possible reasons for the increased expression of synaptophysin‐immunoreactivity may be the markedly increased intramuscular innervation. In fact, in our previous study, we reported that the amount of the smooth muscle increased in parallel the innervations of the muscle layer (Bayram et al., 2002).…”