Pituitary adenylate cyclase-activating peptide (PACAP) immunoreactivity distribution in the small intestine of the adult New Hampshire chicken.
We conducted a study in which we demonstrated by means of immunoperoxidase and immunofluorescence methods the presence of pituitary adenylate cyclase-activating peptide 38 (PACAP-38) immunoreactivity in the small intestine of adult New Hampshire chickens and its co-localization with VIP. In particular we describe for the first time the presence of PACAP-positive cells in the epithelium of crypts and villi. Using double immunostaining, we observed that these two peptides were widely co-localized in the nerve structures of duodenum and jejunum with the exception of the ileum, where we noticed a faint co-localization regarding the nerve fibers of the lamina propria of the villi. Furthermore, the two peptides were occasionally co-stored in the epithelial cells of the mucosa. Our findings suggest that in the chicken small intestine, PACAP can be considered, not only as a neuromodulator released by nerve elements, but also as a gut hormone secreted by endocrine cells, and it appears likely to have a role in the regulation of important intestinal physiological functions.
Pirone
Andrea
A
Dipartimento di Produzioni Animali, Università di Pisa, Pisa 56126, Italy. apirone@vet.unipi.it
Baoan
Ding
D
Piano
Ilaria
I
Della Santina
Luca
L
Baglini
Alessandro
A
Lenzi
Carla
C
D000818:Animals; D002645:Chickens; D004847:Epithelial Cells / Q000378:metabolism; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000166:cytology / Q000294:innervation / Q000378:metabolism*; D009092:Mucous Membrane / Q000378:metabolism; D009412:Nerve Fibers / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000032:analysis; D009928:Organ Specificity; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000032:analysis / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000032:analysis / Q000378:metabolism
D018377:Neurotransmitter Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D014660:Vasoactive Intestinal Peptide