Expression of vasoactive intestinal polypeptide, substance P and neuropeptide Y in jejunal enteric nerves is altered in rabbits suffering from long term Trichinella spiralis infection: an immunohistochemical study

Abstract

ABSTRACT:In the early intestinal stage of infection with the nematode Trichinella spiralis alterations in gut motility and chemical code of enteric neurons are observed. The present study was designed to characterize the changes in expression pattern of vasoactive intestinal polypeptide (VIP), substance P (SP) and neuropeptide Y (NPY) in enteric nerves of the rabbit jejunum occurring during long-lasting trichinellosis (35 and 42 days). Sections of the jejunum from healthy and T. spiralis-infected rabbits were processed for double immunocytochemistry in which antibodies against protein gene product 9.5 were used as a pan-neuronal marker and mixed with antisera raised against VIP, SP or NPY. At 35 and 42 days post infection a marked decrease of VIP-, SP-and NPY-immunoreactive (IR) jejunal myenteric neurons was found, whereas the expression of these neuropeptides in submucous neurons was unchanged. In the myenteric plexus and the jejunal circular muscle of T. spiralis-infected rabbits a significant reduction of VIP-IR (but not SP-IR) nerve fibres was noted. In the longitudinal muscle of the jejunum from animals with long-lasting trichinellosis the density of SP-IR nerve terminals was decreased, whereas the number of VIP-containing nerve fibres was unchanged. Long-lasting trichinellosis had no influence on NPY-IR nerve fibres in both circular and longitudinal smooth muscles. The number of NPY-positive (but not VIP-and SP-IR) nerve fibres supplying mucosa and blood vessels was decreased in T. spiralis-infected animals. These data indicate that during long-lasting trichinellosis expression of neuropeptides in jejunal enteric neurons is changed. A possible involvement of VIP and SP in persistent intestinal dysmotility and NPY in altered fluid secretion is discussed.

Traumatic stress‐induced persistent changes in DNA methylation regulate neuropeptide Y expression in rat jejunum

“…Earlier studies have shown that NPY‐positive nerve fibers and neuronal cell bodies are present in the submucosal layer as well as the myenteric plexus . Similarly, we also observed NPY immunoreactive cells in the myenteric plexus surrounding the jejunum and the network of beaded fibers spread over the myenteric plexus through the villi.…”

Prenatal programming of the small intestine in piglets: the effect of supplementation with 3-hydroxy-3-methylbutyric acid (HMB) in pregnant sows on the structure of jejunum of their offspring

“…Its higher presence with the connection of improved intestinal barrier and antiinflammatory and anti-bacterial properties after the HMB supplementation can help to keep a healthy gut (Xiong et al, 2019). Moreover, other studies on several animals have showed that VIP expression is changed by the inflammatory process, which correlates with altered smooth muscle contractility (Arciszewski et al, 2009).…”