Evolutionary aspects of “brain-gut peptides”: An immunohistochemical study

Changes in the serotonin‐, somatostatin‐ and motilin‐immunoreactive cells in the gastrointestinal tract of the bullfrog,Rana catesbeiana, at various developmental stages

“…Buchan (1986) reported that the motilin containing cells within the intestine of the axolotl (Ambystroma mexicanum). This is the first time that this peptide has been detected outside mammals, but in most amphibian species, they were not detected in the GIT (Buchan et al, 1981;El-Sahly et al, 1981;Fujita et al, 1981). As in previous works, motilin-immunoreactive cells were not found in the present study.…”

An immunohistochemical study of the endocrine cells in the gastrointestinal mucosa of the Caiman latirostris.

“…The GRP molecule contains 27 amino acid residues as compared with 14 residues found in bombesin and nine of the carboxyl terminal amino acids occupy identical positions in the two molecules. Because of the sequence similarity in the carboxyl-termini of both peptides, the GRP antiserum used consistently cross-reacted with the bombesin antiserum (YANAIHARA et al, 1981 ;BUFFA et al, 1982). GRP-immunoreactive cells have also been reported in the avian proventriculus (BUFFA et al, 1982 ;YAMADA et al, 1985) and gizzard (YAMADA et al, 1986a).…”

“…They were not observed in the alligator gastrointestinal tract (BUCHAN et al, 1983) nor in the small intestine of snakes (MASINI, 1986), and attempts to demonstrate motilin-immunoreactive cells in eleven teleost fishes have failed (LANCER et al, 1979). In addition, motilinimmunoreactive cells have been observed in the duodenum of the axolotl, Ambystom mexicanum (BUCHAN 1986), but not in any of the other amphibian species examined (BUCHAN et al, 1980 ;FUJITA et al, 1981 ;BUCHAN, 1986). Immunoreactive cells have been demonstrated in the small intestine of only one reptilian species, the grass lizard (EL-SALHY and GRIMERIUS,1981).…”

Immunocytochemical Localization of Glucagon‐Related Peptides in the Cerebral Ganglion of the Protochordate Ascidian, Styela plicata

“…On the contrary, S-and PHI-like ascidian substances can be considered as members of the 'brain-gut' peptide group because of their additional presence in the alimentary tract (26)(27)(28). These data suggest the occurrence of a 'brain-gut axis' also in protochordates likewise demonstrated in vertebrates and invertebrates (29)(30)(31)(32).…”