Ghrelin in the gastroenteric tract of birds: immunoreactivity expression

In this study we have clearly demonstrated that ghrelin producing cells exist in the chicken gastrointestinal tract. The distribution pattern and morphological character- istics of ghrelin-ic suggest that they correspond to endocrine type cells. However, further investigations are required in order to identify the specific cell types according to the current classification (Solcia et al., 2000). In the frog stomach ghrelin endocrine cells have been observed in the mucosa and in pit-associated glands (Galas et al., 2002). In the rat and human stomach ghrelin-producing endocrine cells have been identified as X/A like cells of the oxyntic mucosa (Kojima et al., 1999; Date et al., 2000). These results indicate that chicken ghrelin is also evolutionally conserved both in its distribution and in its aminoacidic sequence.