Jackson D M, Jenkins O F, Malor R, Christie M J, Gregory P
Naunyn Schmiedebergs Arch Pharmacol. 1983 Dec;324(4):271-4. doi: 10.1007/BF00502622.
The effects of L-Dopa + benserazide (L-Dopa + B) treatment on pre- and postsynaptic dopamine (DA) receptors were studied. Mice treated once daily P.O. with L-Dopa (200 mg/kg) + B (50 mg/kg) or vehicle for 10 days were used on the 11th day. After premedication with reserpine and alpha-methyltyrosine (alpha-MT), apomorphine (0.5-2.0 mg/kg) produced locomotor stimulation which was of equal intensity in the 3 treatment groups, even when the treatment dose of L-Dopa was increased to 400 mg/kg per day. In contrast, low doses of apomorphine (0.1-0.5 mg/kg) produced locomotor depression in B- and vehicle-treated mice but not in L-Dopa + B-treated mice. In rats treated I.P. twice daily with L-Dopa (200 mg/kg) + B (50 mg/kg), B (50 mg/kg) or vehicle for 12 days, apomorphine produced an equivalent degree of stereotypy on the 13th day in each of the 3 treatment groups. There were no treatment group differences in the binding of [3H]-spiperone or [3H]-leu-enkephalin to rat striatal membranes. The data suggest that long-term L-Dopa + B treatment of mice and rats does not change the sensitivity of postsynaptic DA receptors but may affect the sensitivity of DA autoreceptors.
研究了左旋多巴+苄丝肼（L-Dopa + B）治疗对突触前和突触后多巴胺（DA）受体的影响。第11天使用每日经口给予左旋多巴（200 mg/kg）+ B（50 mg/kg）或赋形剂，连续给药10天的小鼠。在用利血平和α-甲基酪氨酸（α-MT）进行预处理后，阿扑吗啡（0.5 - 2.0 mg/kg）产生的运动刺激在3个治疗组中强度相同，即使左旋多巴的治疗剂量增加到每天400 mg/kg。相反，低剂量的阿扑吗啡（0.1 - 0.5 mg/kg）在B处理组和赋形剂处理组的小鼠中产生运动抑制，但在左旋多巴+ B处理组的小鼠中未产生。在每天经腹腔注射给予左旋多巴（200 mg/kg）+ B（50 mg/kg）、B（50 mg/kg）或赋形剂，连续给药12天的大鼠中，第13天阿扑吗啡在3个治疗组中的每一组产生的刻板行为程度相当。[3H]-螺哌隆或[3H]-亮氨酸脑啡肽与大鼠纹状体膜的结合在各治疗组之间没有差异。数据表明，对小鼠和大鼠长期进行左旋多巴+ B治疗不会改变突触后DA受体的敏感性，但可能会影响DA自身受体的敏感性。
