Intranasal 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) Administration Hampered Contractile Response of Dopamine in Isolated Rat Ileum
Rattachement africain : pt, at, br. Niveau de preuve : code pays fourni par la source.
Le résumé fourni par la source
Background: Gastrointestinal (GI) disturbances occur frequently in the early premotor stage of Parkinson’s disease (PD). These GI impairments are associated, at least in part, with dopaminergic dysfunction in the myenteric plexus. However, the enteric nervous system (ENS) pathophysiology underlying GI dysfunction in PD has been overlooked. Objectives: The aim of this study was to evaluate the premotor GI disturbances in rats submitted to intranasal (i.n.) MPTP, a valid experimental model of the premotor stage of PD. Methods: Ileum segments from male Wistar rats (21 weeks old) were collected 12 days following the i.n. MPTP administration for functional studies. Isometric contractile concentration–response (CR) curves (cumulative) for dopamine (DA) were performed in both the presence and absence of sulpiride, a selective dopamine D2-like receptor (D2R) antagonist. Results: Functional studies showed that DA induced a concentration-dependent contractile response in the ileum, which exhibited marked contraction at lower concentrations (0.01–0.9 µM) and relaxation at higher concentrations (3–90 µM). MPTP significantly attenuated both the contraction and the ensuing relaxation. Furthermore, sulpiride significantly reduced the contractile response to DA in the control group and blocked the relaxation in the MPTP group. The MPTP-induced dysmotility occurred with preserved DA homeostasis, as shown by normal DA, TH, and D2R ileal levels in the MPTP group. However, MPTP seemed to impose a decrease in S100β and GFAP (enteroglial markers) immunostaining in the ileal myenteric plexus. Conclusions: In summary, we provide pioneering functional, neurochemical, and morphological evidence showing that rats submitted to the i.n. MPTP model exhibited premotor DA-dependent ileum motile dysfunction accompanied by enteroglial disturbance within the myenteric plexus, but with preserved DA markers.
Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.
Le contrôle bibliographique ouvert
DOI retrouvé dans Crossref DOI retrouvé ; titre concordant.
- Titre Crossref
- Intranasal 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) Administration Hampered Contractile Response of Dopamine in Isolated Rat Ileum
- Date Crossref
- 30/09/2025
- Éditeur
- MDPI AG
- Type
- journal-article
Ce recoupement confirme des métadonnées liées au DOI. Il ne confirme ni la méthode ni les conclusions de l’étude, et il ne compte pas comme une seconde source scientifique indépendante.
Où se fait cette recherche
-
University of Coimbra Centre for Innovative Biomedicine and Biotechnology (CIBB) pays non établi dans la noticeUniversité ou école supérieure
-
Polytechnic Institute of Coimbra pays non établi dans la noticeUniversité ou école supérieure
-
Universität Innsbruck pays non établi dans la noticeUniversité ou école supérieure
-
Universidade Federal de Santa Catarina pays non établi dans la noticeUniversité ou école supérieure
-
Faculty of Medicine Institute of Pharmacology and Experimental Therapeutics pays non établi dans la noticeUniversité ou école supérieure
-
University of Innsbruck Department of Psychiatry pays non établi dans la noticeUniversité ou école supérieure
-
Federal University of Santa Catarina (UFSC) Department of Pharmaceutical Sciences pays non établi dans la noticeUniversité ou école supérieure
-
Faculty of Pharmacy pays non établi dans la noticeUniversité ou école supérieure
Centre for Innovative Biomedicine and Biotechnology (CIBB) — University of Coimbra, Polytechnic Institute of Coimbra et Universität Innsbruck, avec 5 autres affiliations.
Une affiliation ne permet pas de déduire la nationalité d’un auteur.