Puri S, Ray A, Chakravarti A K, Sen P A
Department of Pharmacology, University College of Medical Sciences, Shahdara, Delhi, India.
Pharmacol Biochem Behav. 1994 Mar;47(3):749-52. doi: 10.1016/0091-3057(94)90184-8.
The involvement of dopaminergic (DA) receptors and their possible interactions were evaluated during stress ulcer formation in rats. The DA1 antagonist SCH 23390 (0.025, 0.05, or 0.1 mg/kg) produced only marginal aggravations in gastric stress pathology when compared to vehicle controls. The DA2 antagonist sulpiride (10 or 50 mg/kg) had dose-related effects. The lower dose aggravated whereas the higher dose attenuated stress ulcerogenesis. The DA2 agonist bromocriptine (2.5 or 5.0 mg/kg), however, attenuated gastric stress ulcers. Pretreatment of rats with the DA depletor alpha-methyl-para-tyrosine or the DA1-antagonist SCH23390 clearly neutralized the stress ulcer-attenuating effects of bromocriptine. These results reaffirm a gastric cytoprotective role for DA and further suggest that DA1-DA2 receptor interactions are crucial during DAergic regulation of gastric mucosal integrity during stress.
在大鼠应激性溃疡形成过程中,对多巴胺能(DA)受体的参与及其可能的相互作用进行了评估。与溶剂对照组相比,DA1拮抗剂SCH 23390(0.025、0.05或0.1 mg/kg)仅使胃应激病理有轻微加重。DA2拮抗剂舒必利(10或50 mg/kg)具有剂量相关效应。较低剂量会加重而较高剂量会减轻应激性溃疡的发生。然而,DA2激动剂溴隐亭(2.5或5.0 mg/kg)可减轻胃应激性溃疡。用DA耗竭剂α-甲基-对-酪氨酸或DA1拮抗剂SCH23390预处理大鼠,可明显抵消溴隐亭的应激性溃疡减轻作用。这些结果再次证实了DA对胃的细胞保护作用,并进一步表明,在应激期间DA能调节胃黏膜完整性的过程中,DA1-DA2受体相互作用至关重要。