Isolated blood ring assays were used to study the changes of dopamine receptors in rat aorta vascular smooth muscles after oral L dopa.

• 采用离体血管环的方法对长期服用非亚型特异性拟多巴胺类药物左旋多巴后大鼠主动脉平滑肌中多巴胺受体两亚型（DA1，DA2）的变化进行了观察。