Alterações na motilidade gastrintestinal no modelo de doença de Parkinson induzida por 6-OHDA em ratos

Abstract

Gastrointestinal disorders such as delayed gastric emptying (GD) are one of the physiological changes commonly found in patients with PD, reducing therapeutic responses in view of a decrease in the absorption of nutrients and drugs, which may aggravate the patient's clinical condition. In this study, the effects of PD induced on changes in gastrointestinal motility (Gastric Emptying - EG, Intestinal Transit - TI and Gastric Complacency - CG) and neural pathways involved in such alterations in rats were evaluated. 96 male Wistar rats (250-300 g) were divided into groups: Control (saline) and DP (6-OHDA), the DP group undergoing intrastriatal injection of 6-OHDA (21 μg / animal). The induction of PD was validated by administration of apomorphine (3mg / kg). On the 14th day after PD induction, studies of EG were performed at the 10, 20 or 30 min postprandial time, the IT studies in the 20 min and CG time. To determine the EG rate, 1.5ml of a test meal (red-phenol 0.5mg / ml in glucose-5%) was administered via gavage. TI was determined with direct administration of the meal to the duodenum. CG was evaluated using a barostat system at 4, 8 and 12 cm of gastric distension pressure. Surgeries of vagotomy and splanchnotomy were performed in order to investigate the possible involvement of these pathways in the gastrointestinal alterations through PD. Data, mean ± SEM, were analyzed by Student's t-test (P <0.05). DP delayed the EG in 24.85% in the time 10min, 23,96% in the time 20min and 19,07% in the time 30min. The DP also promoted a delay of 30.93% in IT. There were no significant variations in CG. It was verified that the delay of gastric emptying can be reversed by a pre - treatment of vagotomy and splanchnotomy and celiac gangliectomy, suggesting the involvement of such pathways in the delay of the gastric emptying observed in the DP group. Therefore, the results suggest that the 6-OHDA induction model of PD is able to promote delayed gastric emptying, delayed intestinal transit, however, has no influence on gastric compliance and that delayed gastric emptying was reversed with Preoperative treatment of vagotomy and splanchnotomy.