TY - JOUR
T1 - Postnatal development of the dopaminergic signaling involved in the modulation of intestinal motility in mice
AU - Zizzo, Maria Grazia
AU - Cavallaro, Giacomo
AU - Auteri, Michelangelo
AU - Caldara, Gaetano
AU - Amodeo, Ilaria
AU - Mastropaolo, Mariangela
AU - Nuzzo, Domenico
AU - Di Carlo, Marta
AU - Fumagalli, Monica
AU - Mosca, Fabio
AU - Mule, Flavia
AU - Serio, Rosa
PY - 2016/9/1
Y1 - 2016/9/1
N2 - Background:Since antidopaminergic drugs are pharmacological agents employed in the management of gastrointestinal motor disorders at all ages, we investigated whether the enteric dopaminergic system may undergo developmental changes after birth.Methods:Intestinal mechanical activity was examined in vitro as changes in isometric tension.Results:In 2-d-old (P2) mice, dopamine induced a contractile effect, decreasing in intensity with age, replaced, at the weaning (day 20), by a relaxant response. Both responses were tetrodotoxin (TTX)-insensitive. In P2, dopaminergic contraction was inhibited by D1-like receptor antagonist and mimicked by D1-like receptor agonist. In 90-d-old (P90) mice, the relaxation was reduced by both D1- and D2-like receptor antagonists, and mimicked by D1- and D2-like receptor agonists. In P2, contraction was antagonized by phospholipase C inhibitor, while in P90 relaxation was antagonized by adenylyl cyclase inhibitor and potentiated by phospholipase C inhibitor. The presence of dopamine receptors was assessed by immunofluorescence. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed a significant increase in D1, D2, and D3 receptor expression in proximal intestine with the age.Conclusion:In mouse small intestine, the response to dopamine undergoes developmental changes shifting from contraction to relaxation at weaning, as the consequence of D2-like receptor recruitment and increased expression of D1 receptors.
AB - Background:Since antidopaminergic drugs are pharmacological agents employed in the management of gastrointestinal motor disorders at all ages, we investigated whether the enteric dopaminergic system may undergo developmental changes after birth.Methods:Intestinal mechanical activity was examined in vitro as changes in isometric tension.Results:In 2-d-old (P2) mice, dopamine induced a contractile effect, decreasing in intensity with age, replaced, at the weaning (day 20), by a relaxant response. Both responses were tetrodotoxin (TTX)-insensitive. In P2, dopaminergic contraction was inhibited by D1-like receptor antagonist and mimicked by D1-like receptor agonist. In 90-d-old (P90) mice, the relaxation was reduced by both D1- and D2-like receptor antagonists, and mimicked by D1- and D2-like receptor agonists. In P2, contraction was antagonized by phospholipase C inhibitor, while in P90 relaxation was antagonized by adenylyl cyclase inhibitor and potentiated by phospholipase C inhibitor. The presence of dopamine receptors was assessed by immunofluorescence. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed a significant increase in D1, D2, and D3 receptor expression in proximal intestine with the age.Conclusion:In mouse small intestine, the response to dopamine undergoes developmental changes shifting from contraction to relaxation at weaning, as the consequence of D2-like receptor recruitment and increased expression of D1 receptors.
UR - http://www.scopus.com/inward/record.url?scp=84983775719&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84983775719&partnerID=8YFLogxK
U2 - 10.1038/pr.2016.91
DO - 10.1038/pr.2016.91
M3 - Article
AN - SCOPUS:84983775719
VL - 80
SP - 440
EP - 447
JO - Pediatric Research
JF - Pediatric Research
SN - 0031-3998
IS - 3
ER -