Identification and differential distribution of CART in the small intestine depending on the diet.

Abstract

This study was aimed at identifying and locating cocaine- and amphetamine-regulated transcript (CART) in the small intestine of broilers in relation to the diet. The feeding regime of the chicks was based on diets largely consisting of maize and one of four protein sources: post-extraction soya bean meal (SBM) or non-GM seed meal - meal from traditional variety of soy seeds Glicine max (FFS) and meal from seeds of Lupinus angustifolius (LA) and Lupinus luteus L (LY). The presence of cocaine- and amphetamine-regulated transcript immunoreactive (CART-IR) in the wall of the small intestine of the chicks was determined on the basis of staining patterns produced by the immunohistochemical method (IHC). CART-IR structures were found in the myenteric plexus (MP), submucosus plexus (SP), in endomucosal fibres, and fibres innervating miocytes and blood vessels in the muscularis membrane and adipocytes of the white adipose tissue (WAT) located on the perimeter of the serous membrane and single cells of the diffuse neuroendocrine system. Based on microscopic observation and result analysis, the lowest number of CART-IR structures was identified in the group that was fed the SBM-based diet. This study confirms previous observations concerning CART distribution in the gastrointestinal tract (GIT) of animal and broadens current knowledge by inclusion of chicken in the list of CART-positive species. Moreover, this work provides evidence that dietary composition can be a factor that stimulates post-prandial CART secretion in intestinal nerve structures.