[Participation of peripheral sensory structures of autonomic nervous system in the mechanisms of neuroimmune interactions].

On the basis of the electrophysiological research carried out with immunohystochemical methods on rats, it is found, that introduction of products of mast cell degranulation into blood as well as endogenous release of mast cell mediators with either the compound 48/80 or introduction of egg albumin to presensitized rats, enhances activity of mesenteric afferent nerve fibers. The obtained data provide evidence that intestinal afferents contribute an early signal to the brain regarding potential pathogens. The question of whether or not the intrinsic enteric neurons are involved in these processes, however, has not been carefully studied. So we investigated this problem and found that the enteric neurons express receptor of innate immunity TLR4 and nociceptive vanilloid receptor TRPV1, by means ofimmunohistochemical method. The analysis of neurons distribution revealed that vanilloid receptors are expressed by neurons localized mainly in myenteric plexus whereas TLR4-immunoreactive neurons generally are present in submucous plexus. It is also established coexpression of both receptors in the single intrinsic enteric neuron. In conclusion, our findings indicate that sensory terminals of external afferent fibers as well as intrinsic neurons of intestine can modulate reactions of the organism to endotoxins and thus may be involved in reception of inflammatory and immune responses.